Surgical stapling instrument with an articulatable end effector

ABSTRACT

In various embodiments, a surgical instrument can comprise an end effector including a channel configured to support a staple cartridge and, in addition, an anvil pivotable between open and closed positions relative to the staple cartridge channel. The surgical instrument can further comprise a closure tube configured to at least partially surround the anvil and the staple cartridge channel to hold the anvil in a closed position. The closure tube can extend around the anvil a greater distance than the staple cartridge channel. The surgical instrument can further comprise a shaft and, in addition, an articulation joint pivotably connecting the end effector to the shaft. The articulation joint can further comprise a floating guide member which can guidably support a knife bar extending into the end effector and, at the same time, move independently of the end effector and the shaft to provide such support.

CROSS REFERENCE TO RELATED APPLICATION

The present application is a continuation-in-part application claimingthe benefit under 35 U.S.C. §120 of co-pending U.S. patent applicationSer. No. 12/008,266, entitled SURGICAL STAPLING INSTRUMENT WITH A FIRINGRETURN MECHANISM, filed on Jan. 10, 2008, which is acontinuation-in-part application of U.S. patent application Ser. No.11/821,277, entitled SURGICAL STAPLING INSTRUMENTS, filed on Jun. 22,2007, the entire disclosures of which are hereby incorporated byreference herein.

BACKGROUND

1. Field of the Invention

The present invention generally relates to surgical stapling instrumentsand, more particularly, to surgical staplers having a closing system forclosing an end effector and a firing system for deploying staples.

2. Description of the Related Art

As known in the art, surgical staplers are often used to deploy staplesinto soft tissue in order to reduce or eliminate bleeding from the softtissue, especially as the tissue is being transected, for example.Surgical staplers, such as an endocutter, for example, can comprise anend effector which can be moved, or articulated, with respect to anelongate shaft assembly. End effectors are often configured to securesoft tissue between first and second jaw members where the first jawmember often includes a staple cartridge which is configured toremovably store staples therein and the second jaw member often includesan anvil. Such surgical staplers can include a closing system forpivoting the anvil relative to the staple cartridge. These closingsystems, however, do not prevent the end effector from being articulatedrelative to the shaft assembly after the jaw members have been closed.As a result, when the end effector is articulated, the end effector mayapply a shear force to the soft tissue captured between the jaw members.

Surgical staplers, as outlined above, can be configured to pivot theanvil of the end effector relative to the staple cartridge in order tocapture soft tissue therebetween. In various circumstances, the anvilcan be configured to apply a clamping force to the soft tissue in orderto hold the soft tissue tightly between the anvil and the staplecartridge. If a surgeon is unsatisfied with the position of the endeffector, however, the surgeon must typically activate a releasemechanism on the surgical stapler to pivot the anvil into an openposition and then reposition the end effector. Thereafter, staples aretypically deployed from the staple cartridge by a driver which traversesa channel in the staple cartridge and causes the staples to be deformedagainst the anvil and secure layers of the soft tissue together. Often,as known in the art, the staples are deployed in several staple lines,or rows, in order to more reliably secure the layers of tissue together.The end effector may also include a cutting member, such as a knife, forexample, which is advanced between two rows of the staples to resect thesoft tissue after the layers of the soft tissue have been stapledtogether.

SUMMARY

In at least one form, a surgical stapler can comprise a channelconfigured to receive a staple cartridge comprising staples removablystored therein, wherein the channel comprises a distal end, a proximalportion, and a stop. The surgical stapler can further comprise an anvilconfigured to deform staples ejected from the staple cartridge, whereinthe anvil comprises a distal end and a proximal portion, wherein theproximal portion of the anvil is pivotably coupled to the proximalportion of the channel, and wherein the anvil is rotatable between anopen position and a closed position. The surgical stapler can furthercomprise a closure member movable between a first position and a secondposition, wherein the closure member is configured to move the anvilbetween the open position and the closed position when the closuremember is moved between the first position and the second position, andwherein the closure member comprises a body, a first camming portionextending from the body a first distance toward the distal end of thechannel, wherein the first camming portion is configured to be at leastpartially positioned around the anvil when the closure member is in thesecond position, and a second camming portion extending from the body asecond distance toward the distal end of the channel, wherein the firstdistance is larger than the second distance, wherein the second cammingportion is configured to be at least partially positioned around thechannel and adjacent to the stop when said closure member is in thesecond position.

In at least one form, a surgical instrument can comprise a shaftcomprising a drive bar and a first guide slot, wherein the first guideslot is configured to receive at least a portion of the drive bar, andan end effector pivotably coupled to the shaft about a pivot joint, theend effector being rotatable about the pivot joint in a first directionand a second direction. The end effector can further comprise a staplecartridge attachment portion configured to receive a staple cartridge, asecond guide slot configured to receive at least a portion of the drivebar, a first recess positioned on a first side of the second guide slot,and a second recess positioned on a second side of said second guideslot. The surgical stapler can further comprise a guide memberconfigured to move independently of the shaft and the end effector, theguide member comprising a third guide slot configured to receive atleast a portion of the drive bar, a first catch positioned on a firstside of the third guide slot, wherein the first catch is configured tobe received in the first recess of the end effector when the endeffector is rotated in the first direction, and a second catchpositioned on a second side of the third guide slot, wherein the secondcatch is configured to be received in the second recess of the endeffector when the end effector is rotated in the second direction.

In at least one form, a surgical instrument can comprise a shaftcomprising a drive bar and a first guide slot, wherein the first guideslot is configured to receive at least a portion of the drive bar, andan end effector pivotably coupled to the shaft about a pivot joint. Theend effector can be rotatable about the pivot joint in a first directionand a second direction, the end effector comprising a staple cartridgeattachment portion configured to receive a staple cartridge. Thesurgical instrument can further comprise a guide member configured tomove independently of the shaft and the end effector, wherein the guidemember can comprise a second guide slot configured to receive at least aportion of the drive bar, and a projection, wherein the shaft comprisesa recess configured to receive the projection, wherein the end effectoris configured to push the guide member toward the shaft and position theprojection in the recess when the end effector is moved in the firstdirection or the second direction, and wherein the recess comprises asidewall configured to limit the movement of the projection relative tothe recess and the shaft.

In at least one form, a surgical instrument can comprise a shaftcomprising a housing, a first guide slot in the housing, and a drive barmovable between a first position and a second position, wherein thefirst guide slot is configured to receive at least a portion of thedrive bar. The surgical instrument can further comprise an end effectorpivotably coupled to the shaft about a pivot joint, wherein the endeffector is rotatable about the pivot joint, and wherein the endeffector comprises a staple cartridge attachment portion configured toreceive a staple cartridge. The surgical instrument can further comprisea guide member configured to move relative to the shaft and the endeffector, the guide member comprising a second guide slot configured toreceive at least a portion of the drive bar, an end portion configuredto be contacted by the end effector, and a datum portion. The drive barcan further comprises a shaft, a drive portion configured to be operablyengaged with a cutting member and move the cutting member within the endeffector when the driver bar is moved between the first position and thesecond position, and a stop configured to be engaged with the datumportion of the guide member to limit the movement of the drive barrelative to the end effector.

In at least one form, a surgical instrument can comprise a handle, ashaft extending from the handle, wherein the shaft comprises a housing,a firing member movable relative to the housing, a cutting memberoperably coupled to the firing member, and an end effector pivotablycoupled to the shaft about a pivot joint, wherein the end effector isrotatable about the pivot joint. The end effector can further comprise astaple cartridge attachment portion configured to receive a staplecartridge, and a retraction stop. The surgical instrument can furthercomprise retraction means for moving the firing member and the cuttingmember relative to the staple cartridge attachment portion in a firstdirection and for positioning the cutting member against the retractionstop, and, in addition, drive means for moving the firing member and thecutting member relative to the staple cartridge attachment portion in adirection opposite the first direction a predetermined distance from theretraction stop.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned and other features and advantages of this invention,and the manner of attaining them, will become more apparent and theinvention itself will be better understood by reference to the followingdescription of embodiments of the invention taken in conjunction withthe accompanying drawings, wherein:

FIG. 1 is an elevational view of a surgical instrument in accordancewith an embodiment of the present invention;

FIG. 2 is an elevational view of a handle portion of the surgicalinstrument of FIG. 1;

FIG. 3 is an elevational view of an end effector of the surgicalinstrument of FIG. 1;

FIG. 4 is a top view of the end effector of FIG. 3;

FIG. 5 is a perspective view of an articulation joint of the surgicalinstrument of FIG. 1 with some components of the surgical instrumentremoved;

FIG. 6 is a perspective view of an elongate shaft assembly and thearticulation joint of the surgical instrument of FIG. 1 with somecomponents of the surgical instrument removed;

FIG. 7 is a partial perspective view of the handle portion and theelongate shaft assembly of the surgical instrument of FIG. 1 with somecomponents of the surgical instrument removed;

FIG. 8 is an elevational view of the handle portion of FIG. 2 with somecomponents of the surgical instrument removed;

FIG. 9 is an elevational view of the handle portion of FIG. 2 withadditional components of the surgical instrument removed;

FIG. 10 is an elevational view of an actuator of an articulation lockingmechanism and an end effector closure system of a surgical instrument inaccordance with an alternative embodiment of the present invention withsome components of the surgical instrument removed;

FIG. 11 is an elevational view of the surgical instrument of FIG. 10illustrating the articulation locking mechanism actuator in an unlockedposition and the end effector closure system in an open configuration;

FIG. 12 is an elevational view of the surgical instrument of FIG. 10illustrating the articulation locking mechanism actuator in an unlockedposition and the end effector closure system in a partially closedconfiguration;

FIG. 13 is an elevational view of the surgical instrument of FIG. 10illustrating the articulation locking mechanism actuator in a lockedposition and the end effector closure system in a closed configuration;

FIG. 14 is an elevational view of a closure trigger of an end effectorclosure system of the surgical instrument of FIG. 1;

FIG. 15 is a partial perspective view of the closure trigger of FIG. 15;

FIG. 16 is a partial elevational view of the closure trigger of FIG. 15;

FIG. 17 is a perspective view of a trigger lock of the surgicalinstrument of FIG. 1;

FIG. 18 is an elevational view of the trigger lock of FIG. 17;

FIG. 19 is a detail view of a firing drive of the surgical instrument ofFIG. 1 with some components of the surgical instrument removed;

FIG. 20 is a perspective view of the firing drive of FIG. 19;

FIG. 21 is a partial detail view of a firing trigger, pawl, and tiltermechanism of the firing drive of FIG. 19;

FIG. 22 is an elevational view of the pawl, tilter mechanism, and a pawlreturn spring of the firing drive of FIG. 19;

FIG. 23 is an elevational view of the pawl of FIG. 22;

FIG. 24 is a detail view of the firing drive of FIG. 19 illustrating thepawl pivoted into a position to engage a firing link of the firingdrive;

FIG. 25 is a perspective view of the tilter mechanism of FIG. 22;

FIG. 26 is a perspective view of a frame of the surgical instrument ofFIG. 1;

FIG. 27 is a detail view of a firing drive of a surgical instrument inaccordance with an alternative embodiment of the present invention withsome components of the surgical instrument removed;

FIG. 28 is a detail view of the firing drive of FIG. 27 illustrating apawl of the firing drive disengaged from a firing link;

FIG. 29 is a perspective view of a return mechanism of the surgicalinstrument of claim 1 illustrating the firing trigger in an unactuatedposition with some components of the surgical instrument removed;

FIG. 30 is a partial perspective view of the return mechanism of FIG. 29illustrating the firing trigger in an actuated position with somecomponents of the return mechanism removed;

FIG. 31 is an elevational view of the return mechanism of FIG. 29arranged in the configuration illustrated in FIG. 30;

FIG. 32 is an elevational view of the return mechanism of FIG. 29illustrating a return carriage of the return mechanism in an actuatedposition;

FIG. 33 is a partial perspective view of the return mechanism of FIG. 29with some components of the return mechanism removed;

FIG. 34 is a perspective view of the pawl and firing pin of the firingdrive of FIG. 19;

FIG. 35 is a perspective view of the return mechanism of FIG. 29illustrating the return carriage in an actuated position and the firingtrigger returned to its unactuated position;

FIG. 36 is a partial perspective view of the return mechanism of FIG. 29arranged in the configuration illustrated in FIG. 35 illustrating areturn pin of the return mechanism operably engaged with the firingtrigger;

FIG. 37 is a partial perspective view of the return mechanism of FIG. 29illustrating the firing trigger in an actuated position after rotatingthe return pin;

FIG. 38 is an additional perspective view of the return mechanism ofFIG. 29 arranged in the configuration illustrated in FIG. 37;

FIG. 39 is a partial perspective view of the return mechanism of FIG. 29illustrating the firing trigger returned to its unactuated position;

FIG. 40 is a perspective view of the return mechanism of FIG. 29illustrating the return carriage returned to its unactuated position;

FIG. 41 is a perspective view of the return mechanism of FIG. 29arranged in the configuration of FIG. 40 illustrating the relativerelationship between a biasing spring and the return pin of the returnmechanism with some components of the return mechanism removed;

FIG. 42 is a perspective view of the return mechanism of FIG. 29arranged in the configuration of FIG. 40 illustrating the returncarriage operably engaged with the firing pin of the firing drive andthe return pin of the return mechanism in order to reset the firingdrive and the return mechanism to the their initial configurations;

FIG. 43 is a detail view of a reel of the return mechanism of FIG. 29illustrating the relative relationship between a return band of thereturn mechanism and the stapler frame of FIG. 26;

FIG. 44 is a detail view of the reel of FIG. 43 illustrating therelative relationship between the return band and an alternativeembodiment of the stapler frame of FIG. 26;

FIG. 45 is a perspective view of a return mechanism of a surgicalinstrument in accordance with an alternative embodiment of the presentinvention having an anti-back-up ratchet mechanism;

FIG. 46 is an elevational view of the return mechanism of FIG. 45 havinga return carriage in an unactuated position;

FIG. 47 is a perspective view of the return mechanism of FIG. 45 withsome components of the surgical instrument removed;

FIG. 48 is a perspective view of a return gear, return pin, andanti-back-up pawl of the ratchet mechanism of FIG. 45;

FIG. 49 is another elevational view of the return mechanism of FIG. 45;

FIG. 50 is a perspective view of the articulation joint of FIG. 5;

FIG. 51 is a perspective view of the articulation joint of FIG. 5 withsome components of the surgical instrument removed;

FIG. 52 is a perspective view of the articulation joint of FIG. 5 withadditional components of the surgical instrument removed;

FIG. 53 is a perspective view of a lock member of the end effector ofFIG. 3;

FIG. 54 is another perspective view of the end effector lock member ofFIG. 53;

FIG. 55 is a bottom view of the end effector lock member of FIG. 53;

FIG. 56 is an elevational view of the end effector lock member of FIG.53;

FIG. 57 is a partial perspective view of an articulation joint of aprevious surgical instrument;

FIG. 58 is a perspective view of the articulation joint of FIG. 5 withsome components of the end effector and elongate shaft assembly removed;

FIG. 59 is another perspective view of the articulation joint of FIG. 5with some components of the end effector and elongate shaft assemblyremoved;

FIG. 60 is a perspective view of the end effector lock member of FIG. 53operably engaged with a lock member of the elongate shaft assembly;

FIG. 61 is a perspective view of the shaft assembly lock member of FIG.60;

FIG. 62 is a bottom view of end effector lock member of FIG. 53 operablyengaged with the shaft assembly lock member of FIG. 60;

FIG. 63 is a perspective view of an articulation joint of a surgicalinstrument in accordance with an alternative embodiment of the presentinvention with some components of the surgical instrument removed;

FIG. 64 is a top view of an end effector lock member operably engagedwith a shaft assembly lock member of the surgical instrument of FIG. 63;

FIG. 65 is a perspective view of the end effector lock member operablyengaged with the shaft assembly lock member of FIG. 64;

FIG. 66 is a perspective view of the end effector lock member of FIG.64;

FIG. 67 is an elevational view of the end effector lock member of FIG.64;

FIG. 68 is an elevational view of a surgical instrument in accordancewith an embodiment of the present invention with some components of thesurgical instrument removed;

FIG. 69 is an elevational view of the surgical instrument of FIG. 68illustrating a closure trigger in an actuated position;

FIG. 70 is an elevational view of the surgical instrument of FIG. 68illustrating a firing trigger in an actuated position after a firstactuation of the firing trigger;

FIG. 71 is a perspective view of a gear train of a reversing mechanismof the surgical instrument of FIG. 68 for retracting a firing member;

FIG. 72 is an elevational view of the surgical instrument of FIG. 68illustrating the firing trigger in an unactuated position after it hasbeen released from its first actuation;

FIG. 73 is an elevational view of the surgical instrument of FIG. 68illustrating the firing trigger in an actuated position after a secondactuation of the firing trigger;

FIG. 74 is an elevational view of the surgical instrument of FIG. 68illustrating the firing trigger in an unactuated position after it hasbeen released from its second actuation;

FIG. 75 is an elevational view of the surgical instrument of FIG. 68illustrating the firing trigger in an actuated position after a thirdactuation of the firing trigger;

FIG. 76 is another elevational view of the surgical instrument of FIG.68 illustrating a return carriage of the reversing mechanism after ithas been rotated downwardly into an actuated position;

FIG. 77 is a perspective view of a trigger gear, key gear, and a returnpin of the gear train of the reversing mechanism of FIG. 71;

FIG. 78 is a cross-sectional view of the surgical instrument of FIG. 68illustrating the return pin of FIG. 77 operatively engaged with thetrigger gear and the key gear of the reversing mechanism of FIG. 71;

FIG. 79 is a perspective view of the return pin of FIG. 77;

FIG. 80 is another elevational view of the return carriage of FIG. 76 inan actuated position;

FIG. 81 is a perspective view of a firing pin engaged with a pawl of thefiring drive of the surgical instrument of FIG. 68;

FIG. 82 is an elevational view of the return carriage of the surgicalinstrument of FIG. 68 in an actuated position and the reversingmechanism operably engaged with the firing member;

FIG. 83 is an elevational view of the surgical instrument of FIG. 68illustrating the firing trigger in an actuated position after a fourthactuation which has retracted the firing member;

FIG. 84 is a perspective view of the reversing mechanism of FIG. 76 withsome components removed;

FIG. 85 is an elevational view of the surgical instrument of FIG. 68illustrating the firing trigger in an unactuated position after it hasbeen released from its fourth actuation;

FIG. 86 is an elevational view of the surgical instrument of FIG. 68illustrating the return carriage of FIG. 76 rotated upwardly into anunactuated position and also illustrating the closure trigger in itsunactuated position;

FIG. 87 is a perspective view of a surgical instrument in accordancewith an alternative embodiment of the present invention with somecomponents of the surgical instrument removed;

FIG. 88 is a perspective view of a reversing mechanism of the surgicalinstrument of FIG. 87 including a gear train illustrating the directionsin which the gears of the gear train can rotate when a firing member ofthe surgical instrument is advanced;

FIG. 89 is a perspective view of a trigger gear and a return pin of thereversing mechanism of FIG. 88 illustrating the trigger gear incross-section;

FIG. 90 is another perspective view of the trigger gear and return pinof FIG. 89 illustrating the return pin out of operative engagement withthe trigger gear;

FIG. 91 is a perspective view of the trigger gear and return pin of FIG.89 illustrating the return pin re-engaged with the trigger gear;

FIG. 92 is a perspective view of the reversing mechanism of FIG. 88illustrating the directions in which the gears of the gear train rotatewhen the firing member is retracted;

FIG. 93 is a further perspective view of the reversing mechanism of FIG.88;

FIG. 94 is a perspective view of the surgical instrument of FIG. 87illustrating a trigger lock which is configured to engage a gear of thereversing mechanism of FIG. 88 in addition to the trigger;

FIG. 95 is an elevational view of a reversing mechanism of a surgicalinstrument in accordance with an alternative embodiment of the presentinvention illustrating a return carriage in an unactuated position withsome components of the surgical instrument removed;

FIG. 96 is a perspective view of the reversing mechanism of FIG. 95illustrating a trigger gear having a ratchet face and, in addition, akey gear having a ratchet face with some additional components of thesurgical instrument removed;

FIG. 97 is a cross-sectional view of the reversing mechanism of FIG. 95illustrated in the configuration of FIG. 96;

FIG. 98 is a perspective view of a return pin of the reversing mechanismof FIG. 95;

FIG. 99 is an elevational view of the reversing mechanism of FIG. 95illustrating the return carriage in an actuated position;

FIG. 100 is a perspective view of the reversing mechanism of FIG. 95wherein the ratchet faces of the trigger and key gears are engaged withone another;

FIG. 101 is an elevational view of a surgical instrument in accordancewith an alternative embodiment of the present invention including thefiring drive and the reversing drive of the surgical instrument of FIG.68 with some components of the surgical instrument removed wherein thepawl of the firing drive is illustrated as it would appear when it iswithdrawn relative to the firing member;

FIG. 102 is an elevational view of the surgical instrument of FIG. 101illustrating the pawl operably engaged with the firing member;

FIG. 103 is an elevational view of the surgical instrument of FIG. 101illustrating misalignment between the pawl and a recess in the firingmember when the firing member unintentionally backs-up relative to itsintended position;

FIG. 104 is an elevational view of a surgical instrument in accordancewith an alternative embodiment of the present invention including ananti-backup mechanism with some components of the surgical instrumentremoved;

FIG. 105 is a perspective view of a return pin of the anti-backupmechanism of FIG. 104;

FIG. 106 is a detail view of a key extending from the return pin of FIG.105;

FIG. 107 is a perspective view of an indexing element of the anti-backupmechanism of FIG. 104;

FIG. 108 is a perspective view of the return pin of FIG. 105 operablyengaged with the indexing element of FIG. 107;

FIG. 109 is a perspective view of the return pin and the indexingelement illustrating the key of the return pin positioned within a firstaperture in the indexing element;

FIG. 110 a is another perspective view of the return pin key and theindexing element of FIG. 109;

FIG. 110 b is a perspective view of the return pin key depressing theindexing element when the return pin key is moved from the firstaperture to a second aperture of the indexing element;

FIG. 110 c is a perspective view of the key portion of the return pinpositioned within the second aperture of the indexing element;

FIG. 110 d is a perspective view of the return pin key depressing theindexing element when the return pin key is moved from the secondaperture to a third aperture of the indexing element;

FIG. 110 e is a perspective view of the key portion of the return pinpositioned within the third aperture of the indexing element;

FIG. 110 f is a perspective view of the return pin key depressing theindexing element when the return pin key is moved from the thirdaperture to a fourth aperture of the indexing element;

FIG. 110 g is a perspective view of the key portion of the return pinpositioned within the fourth aperture of the indexing element;

FIG. 111 is a cross-sectional view of the indexing element of FIG. 107;

FIG. 112 is a perspective view of an indexing element in accordance withan alternative embodiment of the present invention and a return springoperatively engaged with the indexing element;

FIG. 113 is a cross-sectional view of the indexing element of FIG. 112;

FIG. 114 is a perspective view of an indexing element in accordance withanother alternative embodiment of the present invention;

FIG. 115 is a partial perspective view of a surgical instrumentincluding an anti-backup mechanism in accordance with an alternativeembodiment of the present invention with some components of the surgicalinstrument removed;

FIG. 116 is a cross-sectional view of the anti-backup mechanism of FIG.115;

FIG. 117 is a perspective view of the surgical instrument of FIG. 115illustrating a return carriage of a reversing mechanism in an actuatedposition;

FIG. 118 is a cross-sectional view of the anti-backup mechanism of FIG.115 when the return carriage of FIG. 117 is in its actuated position;

FIG. 119 is a perspective view of a surgical instrument in accordancewith an alternative embodiment of the present invention with somecomponents of the surgical instrument removed to illustrate a switch foractuating a reversing drive of the surgical instrument;

FIG. 120 is a partial elevational view of a surgical instrument inaccordance with another alternative embodiment of the present inventionwith some components of the surgical instrument removed to illustrate aswitch for actuating a reversing drive of the surgical instrument;

FIG. 121 is a partial elevational view of the surgical instrument ofFIG. 120 illustrating a first portion of the switch in an actuatedposition;

FIG. 122 is a partial elevational view of the surgical instrument ofFIG. 120 illustrating a second portion of the switch utilized toposition the first portion of the switch in its actuated position; and

FIG. 123 is a perspective view of an articulation joint rotatablyconnecting an end effector a shaft of a surgical instrument;

FIG. 124 is an elevational view of an end effector of a surgicalstapling instrument illustrating an anvil in an open position;

FIG. 125 is a detail view of a closure tube of the end effector of FIG.124 holding the anvil of the end effector in a closed position;

FIG. 126 is a perspective view of a closure tube in accordance with analternative embodiment;

FIG. 127 is an elevational view of the closure tube of FIG. 126 engagedwith the anvil of FIG. 123 to position the anvil in a partially-closedposition;

FIG. 128 is an elevational view of the closure tube of FIG. 124 holdingthe anvil of FIG. 124 in a fully-closed position;

FIG. 129 is a top view of an articulation joint between a shaft and anend effector of a surgical stapling instrument illustrated with somecomponents removed, the articulation joint further comprising a guidemember which is movable relative to the shaft and the end effector;

FIG. 130 is a top view of a distal portion of the articulation joint ofFIG. 129;

FIG. 131 is a top view of an articulation joint between a shaft and anend effector of an alternative embodiment of a surgical staplinginstrument with some components removed, the articulation joint furthercomprising a guide member which is movable relative to the shaft and theend effector;

FIG. 132 is a perspective view of the articulation joint of FIG. 131with some components removed;

FIG. 133 is a top view of the articulation joint of FIG. 131 with somecomponents removed illustrating the end effector in a straight, orcentered, position;

FIG. 134 is a top view of the articulation joint of FIG. 131illustrating the end effector in an articulated position;

FIG. 135 is an elevational view of the articulation joint of FIG. 131 inthe orientation illustrated in FIG. 133;

FIG. 136 is an elevational view of a drive bar comprising a cuttingmember configured to cut tissue and a driver configured to deploystaples from a staple cartridge;

FIG. 137 is a plan view of the drive bar of FIG. 136;

FIG. 138 is a partial plan view of a staple cartridge of a surgicalstapler;

FIG. 139 is an elevational view of a cutting member and a knife barattached to the knife bar, the knife bar including a stop surfaceconfigured to limit the advancement of the cutting member within an endeffector of a surgical instrument;

FIG. 140 is a cross-sectional view of the articulation joint of FIG. 131illustrated with the knife bar of FIG. 139, the end effector beingarranged in a straight, or centered, configuration and the stop surfacebeing engaged with the guide member of FIG. 131;

FIG. 141 is a cross-sectional view of the articulation joint of FIG. 131illustrated with the knife bar of FIG. 139, the end effector beingarranged in an articulated configuration and the stop surface beingengaged with the guide member of FIG. 131;

FIG. 142 is a schematic of a firing drive of a surgical staplinginstrument, wherein the firing drive comprises a motor, a rack andpinion system drivable by the motor, and a firing rod operably engagedwith the rack, wherein the operation of the motor advances and/orretracts the firing rod

FIG. 143 is an elevational view of a cutting member within the staplecartridge of FIG. 138 positioned against a retraction stop;

FIG. 144 is a detail view of a connection between a firing rod and aknife bar configured to move the cutting member of FIG. 142 within thestaple cartridge of FIG. 138;

FIG. 145 is a graph depicting an encoder error that can be generatedwithin an encoder when the cutting member is retracted against theretraction stop as illustrated in FIG. 143;

FIG. 146 a is a detail view of the connection of FIG. 144 after thecutting member has been positioned against the retraction stop when theend effector is in a straight, or centered, configuration;

FIG. 146 b is a detail view of the connection of FIG. 144 after thecutting member has been positioned against the retraction stop when theend effector is in an articulated configuration;

FIG. 147 is a top view of a lock engaged with a lock member of an endeffector; and

FIG. 148 is a cross-sectional view of the lock and lock member of FIG.147.

Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplifications set out hereinillustrate preferred embodiments of the invention, in one form, and suchexemplifications are not to be construed as limiting the scope of theinvention in any manner.

DETAILED DESCRIPTION

Certain exemplary embodiments will now be described to provide anoverall understanding of the principles of the structure, function,manufacture, and use of the devices and methods disclosed herein. One ormore examples of these embodiments are illustrated in the accompanyingdrawings. Those of ordinary skill in the art will understand that thedevices and methods specifically described herein and illustrated in theaccompanying drawings are non-limiting exemplary embodiments and thatthe scope of the various embodiments of the present invention is definedsolely by the claims. The features illustrated or described inconnection with one exemplary embodiment may be combined with thefeatures of other embodiments. Such modifications and variations areintended to be included within the scope of the present invention.

In various embodiments, a surgical instrument in accordance with thepresent invention can be configured to insert surgical staples into softtissue, for example. In at least one embodiment, referring to FIGS. 1-4,surgical instrument 100 can include handle portion 102, elongate shaftassembly 104, and end effector 106. In various embodiments, referring toFIGS. 3 and 4, end effector 106 can include staple cartridge channel 108and staple cartridge 110, where staple cartridge 110 can be configuredto removably store staples therein. In at least one embodiment, endeffector 106 can further include anvil 112 which can be pivotablyconnected to staple cartridge channel 108 and can be pivoted betweenopen and closed positions by an end effector closure system. In order todeploy the staples from staple cartridge 110, surgical instrument 100can further include a staple driver configured to traverse staplecartridge 110 and a firing drive configured to advance the staple driverwithin the staple cartridge. In various embodiments, anvil 112 can beconfigured to deform at least a portion of the staples as they aredeployed from the staple cartridge. Although various embodiments of anend effector closure system and a firing drive are described in furtherdetail below, several embodiments of end effector closure systems andfiring drives are disclosed in U.S. Pat. No. 6,905,057, entitledSURGICAL STAPLING INSTRUMENT INCORPORATING A FIRING MECHANISM HAVING ALINKED RACK TRANSMISSION, which issued on Jun. 14, 2005, and U.S. Pat.No. 7,044,352, entitled SURGICAL STAPLING INSTRUMENT HAVING A SINGLELOCKOUT MECHANISM FOR PREVENTION OF FIRING, which issued on May 16,2006, the entire disclosures of which are hereby incorporated byreference herein. Also incorporated by reference in its entirety is thedisclosure of the commonly-owned, contemporaneously-filed United StatesPatent Application entitled SURGICAL STAPLING INSTRUMENT WITH ANARTICULATABLE END EFFECTOR, Attorney Docket No. END6607USNP/090248.

In various embodiments, a surgical instrument in accordance with thepresent invention can include a system for moving, or articulating, anend effector relative to an elongate shaft assembly of the surgicalinstrument. In at least one embodiment, referring to FIGS. 3-7, surgicalinstrument 100 can include articulation joint 114 which can movablyconnect end effector 106 and elongate shaft assembly 104. In variousembodiments, articulation joint 114 can permit end effector 106 to bemoved relative to shaft assembly 104 in a single plane or,alternatively, multiple planes. In either event, articulation joint 114can include one or more pivot axes 116 (FIG. 5) about which end effector106 can be articulated. In various embodiments, referring to FIGS. 5 and6, surgical instrument 100 can further include locking mechanism 118which can fix, or lock, the relative relationship between end effector106 and elongate shaft assembly 104. In at least one embodiment, lockingmechanism 118 can include lock member 120 which can be slid relative toend effector 106 and engage end effector 106 in order to prevent, or atleast partially inhibit, relative movement between end effector 106 andshaft assembly 104. In at least one embodiment, lock member 120 can beconfigured to engage at least one of teeth 312 (FIGS. 5 and 6) of endeffector 106 such that the interaction between lock member 120 and teeth312 can prevent, or at least partially inhibit, end effector 106 fromrotating about axis 116 as described in greater detail further below.

In various embodiments, referring to FIGS. 7-9, locking mechanism 118can further include actuator 122 which can be operably connected to lockmember 120. In at least one embodiment, actuator 122 can include pin 124which can be received within slot 121 in lock member 120 such that, whenactuator 122 is slid relative to handle portion 102, pin 124 can abut aside wall of slot 121 and motivate lock member 120 relative to endeffector 106. In at least one embodiment, actuator 122 can be pulledaway from end effector 106, i.e., proximally, to disengage lock member120 from end effector 106. Although not illustrated, other embodimentsare envisioned where actuator 122 can be moved distally, or evenrotated, in order to disengage lock member 120 from end effector 106. Ineither event, locking mechanism 118 can further include return spring126 (FIG. 6) which can be configured to move lock member 120 toward endeffector 106, i.e., distally, to engage lock member 120 with endeffector 106 after actuator 122 has been released. Other lockingmechanisms are disclosed in U.S. patent application Ser. No. 11/100,772,entitled SURGICAL INSTRUMENT WITH ARTICULATING SHAFT WITH SINGLE PIVOTCLOSURE AND DOUBLE PIVOT FRAME GROUND, which was filed on Apr. 7, 2005,U.S. patent application Ser. No. 11/238,358, entitled SURGICALINSTRUMENT WITH ARTICULATING SHAFT WITH RIGID FIRING BAR SUPPORTS, whichwas filed on Sep. 29, 2005, and U.S. patent application Ser. No.11/491,626, entitled SURGICAL STAPLING AND CUTTING DEVICE AND METHOD FORUSING THE DEVICE, which was filed on Jul. 24, 2006, the entiredisclosures of which are hereby incorporated by reference herein.

In various embodiments, referring to FIGS. 1 and 2, actuator 122 can becontoured such that a surgeon can grasp the outer surface of actuator122 and pull actuator 122 proximally as described above. To moveactuator 122, in at least one embodiment, a surgeon may place one handon handle grip 127, for example, and place their other hand on actuator122 so that the surgeon can move actuator 122 relative to handle grip127. In other various embodiments, referring to FIGS. 10-13, actuator122′ can be configured such that a surgeon may only need one hand tooperate the surgical instrument. More particularly, in at least oneembodiment, actuator 122′ can include hooks, or projections, 115extending therefrom which can allow the surgeon to hold handle grip 127with one hand and extend at least one finger from that hand distally togrip at least one projection 115 and pull actuator 122′ proximally asdescribed above. While actuator 122′ is described herein as havingprojections 115, actuator 122, or any other suitable actuator, can alsoinclude projections 115 and/or any other suitable features that canassist a surgeon in operating surgical instrument 100 with one hand. Inat least one embodiment, projections 115 can be at least partiallycomprised of and/or coated with an elastic or ‘soft-touch’ materialwhich can improve the surgeon's grip on projections 115 and can provideother ergonomic benefits to the surgeon. In various embodiments,actuator 122′, for example, can be operably engaged with shaft assembly104 such that end effector 106 and shaft assembly 104 can be rotatedabout a longitudinal axis by actuator 122′. In such embodiments, asurgeon can orient end effector 106 in a surgical site by articulatingend effector 106 as described above and/or rotating end effector 106into position. In at least one embodiment, the surgeon can rotateactuator 122′ by positioning a finger against one of projections 115 andapplying a force thereto. In various embodiments, the surgeon can holdactuator 122′ in position by placing a finger against a projection 115and resisting any undesired motion of actuator 122′ and,correspondingly, end effector 106.

In various embodiments, a surgical instrument in accordance with thepresent invention can include a system for closing, or clamping, an endeffector onto soft tissue, for example. In at least one embodiment,referring to FIGS. 2, 5, 8 and 9, surgical instrument 100 can includeclosure trigger 128, drive link 130, driver 132, and closure tube 134.In various embodiments, upon an actuation of closure trigger 128,closure trigger 128 can be configured to displace drive link 130, driver132, and closure tube 134 distally. More particularly, in at least oneembodiment, drive link 130 can include a first end pivotably connectedto trigger 128 and a second end pivotably connected to driver 132 suchthat the rotation of trigger 128 toward handle grip 127 can drive link130 forward and slide driver 132 along an axis defined by driver guide136 (FIG. 8). In various embodiments, driver 132 can include projections133 extending therefrom which can be slidably received within slots 135in driver guide 136 such that slots 135 can define a path for driver 132as it is moved. In various embodiments, closure tube 134 can be operablyengaged with driver 132 such that, when driver 132 is moved distally asdescribed above, closure tube 134 can engage anvil 112 and pivot anvil112 downwardly. Referring primarily to FIG. 5, closure tube 134 can beconfigured to slide over articulation joint 114 and pivot anvil 112relative to staple cartridge 110. In at least one embodiment, asillustrated in FIG. 9, closure tube 134 can include a proximal endhaving projection 135 extending therefrom which can be received in slot131 in driver 132 such that the displacement of driver 132 istransmitted to closure tube 134.

In various embodiments, as described above, locking mechanism 118 canprevent, or at least partially inhibit, relative movement between endeffector 106 and shaft assembly 104. In circumstances where soft tissueis clamped between anvil 112 and staple cartridge 110, for example,relative movement between end effector 106 and shaft assembly 104 canapply a shear force to the soft tissue clamped therebetween which maydamage it. In various embodiments, referring to FIGS. 10-13, in order toprevent, or at least reduce, relative movement between end effector 106and shaft assembly 104 when end effector 106 is closed, the end effectorclosure system can be configured to engage locking mechanism 118 toprevent actuator 122′ from being moved into its unlocked position. Ineffect, in at least one embodiment, the actuation of closure trigger 128can not only close end effector 106, but it can also prevent lockingmechanism 118 from being unlocked. In various embodiments, referring toFIGS. 10-13, surgical instrument 100′ can include driver 132 which canbe configured to abut, or be positioned closely adjacent to, actuator122′ when driver 132 is moved distally by trigger 128 and therebyprevent actuator 122′ from being moved proximally as described abovewith respect to actuator 122. More particularly, before trigger 132 isactuated, as illustrated in FIGS. 10 and 11, actuator 122′ can be slidproximally in order to slide lock member 120 relative to end effector106 and unlock articulation joint 114. Upon an actuation of trigger of132, however, referring to FIG. 13, driver 132 can be configured toabut, or be positioned adjacent to, actuator 122′ such that actuator122′ cannot be moved proximally to disengage lock member 120 from endeffector 106. As a result, the end effector closure system can preventend effector 106 from being articulated after it has been closed,thereby reducing the possibility that a shear force will be transmittedto the soft tissue clamped therein.

Further to the above, the end effector closure system can providefeedback to the surgeon that the end effector has been closed and, inorder for the surgeon to unlock and articulate the end effector, thesurgeon must first at least partially re-open the end effector beforethe end effector can be articulated. More particularly, owing to theinteraction between driver 132 and actuator 122′ when end effector 106is closed, when a surgeon attempts to pull actuator 122′ proximally tounlock articulation joint 114, driver 132 can substantially preventactuator 122′ from moving thereby signaling to the surgeon that endeffector 106 is closed and end effector 106 must first be opened beforeactuator 122′ can be moved and the articulation joint can be unlocked.In various embodiments, such an end effector closure system can preventthe surgeon from damaging the surgical instrument and/or tissue capturedwithin, or surrounding, the end effector. More particularly, in at leastone embodiment, when closure tube 134 has been advanced to close anvil112 as described above, closure tube 134 may apply a force to anvil 112to maintain anvil 112 in a closed position and, in variouscircumstances, this force can create friction forces within articulationjoint 114 which can inhibit, if not prevent, end effector 106 fromrotating about articulation joint 114. In embodiments without the endeffector closure system described above, if a surgeon attempts toovercome these friction forces without first at least partially openingthe end effector, the surgeon may bend or break one or more componentsof the surgical instrument, for example. In various embodiments of thepresent invention, however, driver 132, for example, may prevent thesurgeon from releasing articulation lock 120 as described above and, asa result, the surgeon may not be afforded the opportunity to unlockarticulation joint 114 let alone articulate end effector 106.

In various embodiments, a surgical instrument in accordance with thepresent invention can include an end effector closure system which canposition anvil 112, for example, in an open position, a closed position,and a partially closed position. In at least one embodiment, a surgeoncan move an anvil 112 into a partially closed position and evaluatewhether the end effector should be repositioned or articulated beforeanvil 112 is moved into its closed position. In such embodiments, anvil112 can be moved relative to soft tissue positioned intermediate anvil112 and staple cartridge 110 without applying a shear force, or at leasta substantial shear force, to the soft tissue before anvil 112 iscompletely closed. In at least one embodiment, anvil 112 can beconfigured such that it does not clamp the soft tissue positionedbetween anvil 112 and staple cartridge 110 when it is in its partiallyclosed position. Alternatively, anvil 112 can be configured to apply alight clamping force to the soft tissue when anvil 112 is in itspartially closed position before applying a larger clamping force whenit is moved into its closed position. In at least one such embodiment,the surgical instrument can include a trigger which can be moved betweena first position (FIG. 11) which corresponds to the open position ofanvil 112, a second position (FIG. 12) which corresponds with itspartially closed position, and a third position (FIG. 13) whichcorresponds with its closed position. In various embodiments, referringto FIGS. 8 and 9, trigger 128 can be pivotably mounted to housing 103 ofhandle portion 102 such that trigger 128 can be rotated about pin 129between its first, second, and third positions. In various embodiments,referring to FIGS. 8, 9, 17 and 18, surgical instrument 100 can furtherinclude trigger lock 148 which can be configured to engage trigger 128and selectively lock trigger 128 in at least one of its first, second,and third positions described above. In at least one embodiment, trigger128 can include pivot end 138 comprising cam surface 140, first notch142, and second notch 144 where trigger lock 148 can be configured toengage first notch 142 and second notch 144. More particularly, surgicalinstrument 100 can further include, referring to FIGS. 8 and 9, triggerlock spring 150 which can be configured to bias follower portion 149 oftrigger lock 148 against cam surface 140 such that when either firstnotch 142 or second notch 144 is aligned with follower portion 149,trigger lock spring 150 can push follower portion 149 into first notch142 or second notch 144, respectively. In at least one embodiment,referring primarily to FIGS. 8 and 9, trigger lock 148 can be pivotablymounted to housing 103 of handle portion 102 via pin 151. In variousembodiments, trigger lock spring 150 can be compressed intermediatebutton portion 152 of trigger lock 148 and housing 103 such that triggerlock spring 150 can rotate trigger lock 148 about pin 151 and biastrigger lock 148 downwardly against cam surface 140 of trigger 128.

Further to the above, in at least one embodiment, first notch 142 can bealigned with follower portion 149 when trigger 132 is moved into itssecond position and anvil 112 is moved into its partially closedposition. In various embodiments, follower portion 149 can be securelyretained within first notch 142 such that trigger lock 148 may need tobe manually disengaged from trigger 132 before trigger 132 can be movedinto its third position and/or returned to its first position. In atleast one embodiment, referring to FIGS. 8 and 9, a surgeon can depressbutton portion 152 of lock member 148 such that lock member 148 isrotated about pin 151 and follower portion 149 is lifted upwardly andout of engagement with trigger 128. In other various embodiments, firstnotch 142 can be configured such that follower portion 149 can slide outof first notch 142 upon an application of force to trigger 132. Ineither event, after follower portion 149 has been disengaged from firstnotch 142, a surgeon can selectively move trigger 132 into its thirdposition or release trigger 132 and allow a trigger spring, for example,to return trigger 132 to its first position. In at least one alternativeembodiment, first notch 142 and follower portion 149 can be configuredsuch that, after trigger 132 has been moved into its second position,trigger 132 must be moved into its third position before it can bereturned into its first position. In either event, in at least oneembodiment, second notch 144 of trigger 132 can be aligned with followerportion 149 when trigger 132 is moved into its third position and anvil112 is moved into its closed position. Similar to first notch 142,second notch 144 can be configured to retain follower portion 149therein until lock member 148 is disengaged from trigger 132 and/or asufficient force is applied to trigger 132 to dislodge follower portion149 from second notch 144. Thereafter, in various embodiments, a triggerspring can move trigger 132 from its third position into its secondposition where the surgeon may be required to, similar to the above,disengage follower portion 149 from first notch 142. In at least onealternative embodiment, first notch 142 can be configured such thatfollower portion 149 can slide past first notch 142 and allow trigger132 to be moved from its third position to its first position withoutrequiring the surgeon to dislodge follower portion 149 from first notch142.

Further to the above, although not illustrated, button portion 152 oflock member 148 can be recessed, for example, within surgical instrumenthousing 103 when closure trigger 128 is in its first position. Inalternative embodiments, button portion 152 can be positioned flushlywith housing 103 or it can extend slightly from housing 103. In eitherevent, in at least one embodiment, button portion 152 can move outwardlyrelative to housing 103 when closure trigger 128 is moved into itssecond position. Such movement can provide visual feedback to thesurgeon that the anvil of the surgical instrument is in its partiallyclosed position. In addition, the movement of button portion 152 canalso be accompanied by audio and/or tactile feedback. In either event, asurgeon can access button portion 152 after it has been moved outwardlysuch that lock member 148 can be disengaged from trigger 128 asdescribed above. In various embodiments, button portion 152 can moveoutwardly even further when trigger 128 is moved from its secondposition to its third position. Similar to the above, such movement canprovide a visual cue to the surgeon that the anvil is now in its closedposition and can be accompanied by audio and/or tactile feedback, asdescribed above. Although button 152 is described above as movingoutwardly as trigger 128 is progressed between its first and thirdpositions, the invention is not so limited. On the contrary, button 152,or any other suitable indicator, can be provide feedback to the surgeonin any suitable manner.

In alternative embodiments, although not illustrated, anvil 112 can beheld, or retained, in more than the three positions described above,i.e., its open, closed, and partially-closed positions. In at least oneembodiment, anvil 112 can be retained in open, closed, and two or moreintermediate positions. In such embodiments, anvil 112 could beprogressed through these intermediate positions and apply anincreasingly greater force to the soft tissue captured in end effector106 as anvil 112 is moved toward its closed position. In at least oneembodiment, similar to the above, trigger 132 could include a pluralityof notches which could correspond with the various intermediatepositions of anvil 112. In various alternative embodiments, although notillustrated, the end effector closure system could include a ratchetassembly which could allow trigger 132 and, correspondingly, anvil 112to be held in a plurality of positions. In such embodiments, anvil 112and trigger 132 could be held in place by a pawl pivotably engaged witha ratchet wheel operably engaged with trigger 132.

In various embodiments, referring to FIGS. 10-13, the relative movementbetween actuator 122′ and handle portion 102′, as described above, canbe limited in order to control the range through which lock member 120can be displaced. More particularly, referring to FIGS. 10 and 11, thedistal portion of actuator 122′ can include projection 123 extendingtherefrom which can be received in cavity 125 where the displacement ofactuator 122′ can be limited by proximal wall 117 and distal wall 119 ofcavity 125. In at least one embodiment, when trigger 128 is in its firstposition, as illustrated in FIGS. 10 and 11, actuator 122 can be movedfrom a distal position in which projection 123 can abut distal wall 119,as illustrated in FIG. 10, into a more proximal position in whichprojection 123 does not abut distal wall 119, as illustrated in FIG. 11.In this more distal position, as described above, lock member 120 can bedisengaged from end effector 106 and end effector 106 can be rotatedrelative to shaft assembly 104. When trigger 128 is in its secondposition, referring to FIG. 12, driver 132 can limit the range of motionof actuator 122′ such that projection 123 cannot be positioned againstproximal wall 117. In at least one embodiment, however, actuator 122′can be moved proximally a sufficient distance to disengage lock member120 from end effector 106. In these circumstances, a surgeon canreposition end effector 106 although anvil 112 may be partially closedonto the soft tissue, for example. When trigger 128 is in its thirdposition, as illustrated in FIG. 13, driver 132 can force actuator 122′distally such that projection 132 abuts, or is positioned adjacent to,distal wall 119 and actuator 122′ cannot be moved sufficiently to unlockarticulation joint 114.

In various embodiments, a surgical instrument in accordance with thepresent invention can include a firing drive configured to advance acutting member and/or staple driver within an end effector as describedabove. In at least one embodiment, referring to FIGS. 8, 9 and 19-25,the firing drive of surgical instrument 100 can include firing trigger160, first firing link 162, second firing link 164, and firing member166. In various embodiments, firing trigger 160 can be operably engagedwith at least one of firing member 166 and firing links 162 and 164 inorder to advance knife bar 168 within elongate shaft assembly 104. In atleast one embodiment, knife bar 168 can be operably engaged with acutting member (not illustrated) and a staple driver (not illustrated)in end effector 106 where the cutting member can be configured to incisetissue, for example, and the staple driver can be configured to deploystaples from staple cartridge 110. Cutting members and staple driversare well disclosed in U.S. Pat. Nos. 6,905,057 and 7,044,352, which havebeen previously incorporated by reference into the present application,and, as a result, these devices are not described in greater detailherein. Other cutting members and staple drivers are disclosed in U.S.patent application Ser. No. 11/541,123, entitled SURGICAL STAPLES HAVINGCOMPRESSIBLE OR CRUSHABLE MEMBERS FOR SECURING TISSUE THEREIN ANDSTAPLING INSTRUMENTS FOR DEPLOYING THE SAME, which was filed on Sep. 29,2006, and U.S. patent application Ser. No. 11/652,169, entitled SURGICALSTAPLING DEVICE WITH A CURVED CUTTING MEMBER, which was filed on Jan.11, 2007, the entire disclosures of which are hereby incorporated byreference herein.

In various embodiments, referring primarily to FIGS. 19 and 20, firingtrigger 160 can be pivotably connected to surgical instrument housing103 (FIGS. 8 and 9) by pin 161. In use, in at least one embodiment,firing trigger 160 can be pivoted about pin 161 in order to advancefiring member 166 and firing links 162 and 164 distally. In variousembodiments, firing trigger 160 can include slots 159, where slots 159can be configured to receive firing pin 172. In various embodiments,when firing trigger 160 is actuated, or rotated, from its positionillustrated in FIG. 2 to a position adjacent handle grip 127, the sidewalls of slots 159 can be configured to engage and advance firing pin172 distally. In at least one embodiment, referring to FIG. 23, thefiring drive can further include pawl 170, where pawl 170 can includeaperture 171. In various embodiments, aperture 171 can be configured toreceive at least a portion of firing pin 172 such that, when firing pin172 is advanced distally by trigger 160, firing pin 172 can advance pawl170 distally as well. In various embodiments, referring to FIG. 24, pawl170 can include tooth 174 and firing member 166 can include recess 167,where recess 167 can be configured to receive tooth 174. In use, whenpawl 170 is advanced distally by firing pin 172 and tooth 174 is engagedwith a side wall of recess 167, pawl 170 can advance firing member 166distally as well. In various embodiments, pawl 170 can be advanceddistally by firing pin 172 along a substantially linear path. In suchembodiments, slots 159 can include arcuate profiles which can, incooperation with firing pin 172, convert the rotational motion of firingtrigger 160 into translational motion of pawl 170. In at least oneembodiment, the force applied to pawl 170 can be substantially, if notentirely, directed in the distal direction. In such embodiments, as aresult, the possibility of pawl 170 becoming bound or stuck againststapler frame 184 can be reduced.

In various embodiments, pawl 170 can be pivoted between a first positionin which pawl 170 is operably disengaged from firing member 166 and asecond position, referring to FIGS. 19 and 20, in which pawl 170 isoperably engaged with firing member 166. Referring primarily to FIGS.21-25, the firing drive can further include tilter mechanism 178 whichcan be configured to pivot pawl 170 between its first and secondpositions. In use, when firing trigger 160 is actuated, pawl 170 can bemoved, at least initially, relative to tilter mechanism 178 such that atleast a portion of pawl 170 can abut tilter mechanism 178 and pivot pawl170 upwardly and into operative engagement with firing member 166. In atleast one embodiment, pawl 170 can include, referring primarily to FIG.23, groove 175 which can be configured to receive projection 179 (FIG.25) extending from the center portion of tilter mechanism 178. In atleast one embodiment, as pawl 170 is advanced distally, proximal wall176 of groove 175 can contact a cam surface on projection 179 and, owingto the force applied to pawl 170 by pivot pin 172, pawl 170 can bepivoted, or rotated, upwardly such that tooth 174 can be positioned inrecess 167 of firing member 166 as described above. After pawl 170 hasbeen pivoted, pawl 170 can drag tilter mechanism 178 distally as pawl170 is advanced toward end effector 106. More particularly, in at leastone embodiment, tilter mechanism 178 can include deformable members 180which can be received within slots 182 in stapler frame 184 such thatthe interaction between deformable members 180 and stapler frame 184 atleast partially inhibits the movement of tilter mechanism 178 relativeto stapler frame 184. Stated another way, owing to static frictionforces between deformable members 180 and the side walls of slots 182, aforce sufficient to overcome these friction forces must be applied totilter mechanism 178 before tilter mechanism 178 can be ‘dragged’relative to stapler frame 184.

After firing trigger 160 has been actuated and firing member 166 hasbeen advanced, trigger 160 can be released and returned to itsunactuated position illustrated in FIG. 2 and pawl 170 can be disengagedfrom firing member 166 and retracted to its starting positionillustrated in FIG. 19. More particularly, in at least one embodiment,surgical instrument 100 can further include a trigger spring (notillustrated) operably engaged with trigger 160 and housing 103, forexample, where the trigger spring can be configured to rotate trigger160 about pin 161 and drive firing pin 172 proximally after pawl 170 hasbeen disengaged from firing member 166. In various embodiments, pawl 170can be disengaged from firing member 166 when it is pivoted from itssecond position, as illustrated in FIG. 24, into its first position, asdescribed above, by tilter mechanism 178. In such embodiments, pawl 170can be moved, at least initially, relative to tilter mechanism 178 suchthat distal wall 177 of groove 175 can contact a second cam surface onprojection 179 and can, owing to a force applied to firing pin 172 bytrigger 160 or return spring 186, rotate pawl 170 downwardly such thattooth 174 of pawl 170 can be disengaged from recess 167 in firing member166. Thereafter, trigger 160 and/or return spring 186 can pull, orretract, pawl 170 relative to firing member 166. In various embodiments,similar to the above, pawl 170 can be configured to drag tiltermechanism 178 proximally within slot 182. As a result of the above, pawl170 does not need to be biased into its first or second positions. Invarious circumstances, pawl 170 can be rotated freely between its firstand second positions without having to overcome a force applied theretoby a biasing spring. In effect, in various embodiments, the force tomove pawl 170 between its first and second positions need only overcomethe gravitational weight of pawl 170 and any frictional forces betweenpawl 170 and the surrounding components of the surgical instrument.

Once pawl 170 has been returned to its original position, in at leastone embodiment, tooth 174 of pawl 170 may no longer be aligned withrecess 167 in firing member 166. On the contrary, referring generally toFIGS. 19 and 20, tooth 174 of pawl 170 can be aligned with recess 163 infirst firing link 162. More particularly, first firing link 162 can bepivotably connected to firing member 166 such that, when firing member166 is advanced distally, as described above, firing member 166 can pullfirst firing link 162 into the position that firing member 166previously occupied. As a result, upon a second actuation firing trigger160, pawl 170 can be pivoted from its first position into its secondposition such that tooth 174 is operably engaged with recess 163 andpawl 170 can advance firing link 162 distally. In at least oneembodiment, firing link 162 can push firing member 166 and knife bar 168distally and, correspondingly, advance the cutting member and the stapledriver distally within end effector 106. Thereafter, pawl 170 can onceagain be pivoted from its second position to its first position and canbe retracted relative to first firing link 162. Once pawl 170 isreturned to its original position for the second time, tooth 174 of pawl170 may no longer be aligned with recess 163 of first firing link 162.On the contrary, similar to the above, tooth 174 can be aligned withrecess 165 in second firing link 164 and the process described above canbe repeated.

Although not illustrated, a surgical instrument in accordance with thepresent invention can include more than two, or less than two, firinglinks in order to advance the cutting member and staple driver to theirdesired positions within end effector 106. In various embodiments, asdescribed in greater detail below, firing member 166 can include morethan one recess 167 such that pawl 170 can directly advance firingmember 166 toward end effector 106 more than once. In at least one suchembodiment, pawl 170 can be retracted after advancing firing member 166distally, as described above, such that, when pawl 170 is once againtilted upwardly, pawl 170 can engage another recess 167 in firing member166 and advance firing member 166 toward end effector 106 once again. Asa result, in at least one embodiment, firing links 162 and 164 may notbe required.

In various embodiments, a surgical instrument can include one or morespring members configured to move pawl 170 into at least one of itsfirst and second positions. In at least one embodiment, referring toFIGS. 27 and 28, the firing drive can include pawl 170′, firing pin 172,and tilter mechanism 178′ where, similar to the above, tilter mechanism178′ can be configured to pivot pawl 170′ upwardly when pawl 170′ isadvanced distally. The firing drive can further include pivot spring 188which can be operably connected to pawl 170′ such that, when pawl 170′is pivoted upwardly into its second position as illustrated in FIG. 27,pawl 170′ can flex, or resiliently bend, pivot spring 188. After pawl170′ has been advanced, pawl 170′ can be pivoted downwardly into itsfirst position by pivot spring 188 as illustrated in FIG. 28. Moreparticularly, owing to potential energy stored in pivot spring 188 whenit is flexed, spring 188 can move pawl 170′ downwardly once pawl 170′ isno longer held in its second position by tilter mechanism 178′ andfiring pin 172. Thereafter, as described above, pawl 170′ can beretracted relative to firing member 166 and/or firing links 162 and 164.In various embodiments, tilter mechanism 178′ may not include a secondcam surface for pivoting pawl 170 into its first position. In suchembodiments, pawl 170′ can be retracted by a force applied to firing pin172 as described above. In various alternative embodiments, although notillustrated, tilter mechanism 178′ and pawl 170′ can also includeco-operating features for pivoting pawl 170′ downwardly into its firstposition.

In various embodiments, referring to FIGS. 19 and 20, surgicalinstrument 100 can further include band 190 which can be configured tomove firing member 166 and firing links 162 and 164 relative to endeffector 106. In at least one embodiment, a first end of band 190 can beconnected to firing member 166, for example, such that, when firingmember 166 is advanced distally, band 190 can be pulled distally aswell. In various alternative embodiments, band 190 can be connected tofirst firing link 162 and/or second firing link 164. In at least oneembodiment, band 190 can be positioned around at least a portion ofreel, or spool, 192 such that when band 190 is pulled by firing member166, band 190 can be deployed, or unwound, from reel 192. In at leastone embodiment, a second end of band 190 can be connected to reel 192such that band 190 cannot be readily disengaged from reel 192 under thenormal operating conditions of surgical instrument 100. In either event,when band 190 is pulled by firing member 166, reel 192 can be rotated inone of a clockwise or counter-clockwise direction, depending on themanner in which band 190 is positioned around reel 192. In order toretract firing member 166, reel 192 can be rotated in an oppositedirection to move firing member 166, and firing links 162 and 164,proximally and wind band 190 around reel 192.

In various embodiments, band 190 can be wound around reel 192 such thatband 190 is wrapped around a substantially cylindrical surface on reel192. In at least one embodiment, the distance between an axis ofrotation of reel 192 and the cylindrical surface can be substantiallyequidistant around the perimeter of reel 192. In these embodiments, themechanical advantage of reel 192 can remain substantially constant asband 190 is pulled proximally as described above and the capacity forreel 192 to apply a pulling force to band 190 can remain substantiallythe same. In alternative embodiments, however, reel 192 can beconfigured to provide a variable mechanical advantage. In at least oneembodiment, reel 192 can include a non-cylindrical surface on which band190 can be wrapped such that the distance between the axis of rotationof reel 192 and the non-cylindrical surface is not equidistant aroundthe perimeter of reel 192. In these embodiments, as a result, thecapacity for reel 192 to apply a pulling force to band 190 can change asband 190 is wound around reel 192. In at least one embodiment, reel 192can act as a cam and can include a shape which can be optimized toprovide additional force to band 190 when it is initially retracted,i.e., when the force to retract the cutting member, for example, can beat its highest.

In various embodiments, referring to FIGS. 29-42, firing trigger 160 canbe selectively engaged with a return mechanism of surgical instrument100. In at least one embodiment, when firing trigger 160 is operablyengaged with firing member 166 via pawl 170, as described above, anactuation of firing trigger 160 can advance firing member 166 distallyand, when firing trigger 160 is operably engaged with firing member 166via band 190, an actuation of firing trigger 160 can retract firingmember 166 proximally. In various embodiments, the return mechanism canbe manually actuated to disengage firing trigger 160 from firing member166 and to operably engage firing trigger 160 with reel 192. In at leastone embodiment, the return mechanism can include return carriage 194which can be pivotably mounted in surgical instrument housing 103 suchthat return carriage 194 can be pivoted between a first, or unactuated,position as illustrated in FIG. 29 and a second, or actuated, positionas illustrated in FIG. 32. In at least one such embodiment, returncarriage 194 can include push button portion 195 which, when a force isapplied thereto, can be configured to move return carriage 194 from itsunactuated position to its actuated position.

When return carriage 194 is positioned in its unactuated positionillustrated in FIGS. 29-31, firing trigger 160 can be configured toadvance firing member 166 as described above and gear portion 158 oftrigger 160 can be operatively engaged with trigger gear 196. In variousembodiments, gear portion 158 and trigger gear 196 can be operablyengaged such that a rotation of trigger 160 about pin 161 can drivetrigger gear 196 about an axis defined by return pin 198. In at leastone embodiment, when return carriage 194 is in its unactuated position,trigger gear 196 can be configured to rotate freely about return pin 198such that the rotation of trigger gear 196 is not transmitted, or atleast not substantially transmitted, to return pin 198. Moreparticularly, referring to FIG. 30, key 199 of return pin 198 can bebiased out of engagement with trigger gear 196 such that the rotation oftrigger gear 196 is not transmitted to key gear 206 and reel 192. As aresult, an actuation of trigger gear 196 does not rotate, or at leastsubstantially rotate, reel 192 when return carriage 194 is in itsunactuated position.

After the cutting member and the staple driver have been advanced withinend effector 106, return carriage 194 can be moved into its actuatedposition. In various embodiments, referring to FIG. 30, reel 192 caninclude cam member 202 extending therefrom which can contact returncarriage 194 and rotate return carriage 194 downwardly. In at least oneembodiment, cam member 202 can contact return carriage 194 during thefinal actuation of trigger 160 which advances the cutting member andstaple driver within end effector 106. In at least one such embodiment,cam member 202 can contact return carriage 194 after the third actuationof firing trigger 160. In various embodiments, referring to FIGS. 32-35,when gear carriage 194 is moved into its actuated position, returncarriage 194 can be configured to operably engage trigger gear 196 withreel 192. In at least one embodiment, referring to FIGS. 33 and 35,return carriage 194 can include biasing spring 200 where, when returncarriage 194 is in its unactuated position, spring 200 can be located inthe position illustrated in FIG. 33 and, when return carriage 194 ismoved into its actuated position illustrated in FIG. 35, spring 200 cancontact return pin 198 and bias return pin 198 toward trigger gear 196.In at least one embodiment, referring to FIG. 31, trigger gear 196 caninclude D-shaped cavity 197 therein which can, under certaincircumstances explained below, receive key 199 extending from return pin198 and operably engage trigger gear 196 with key gear 206 and reel 192.In various embodiments, the movement of return carriage 194 into itsactuated position can be accompanied by an audio and/or tactile feedbackto inform the surgeon that the return mechanism of the surgicalinstrument has been engaged with trigger 160.

Further to the above, when return pin 198 is slid toward trigger gear196, D-shaped cavity 197 can be positioned such that key 199 does notimmediately enter cavity 197. On the contrary, referring to FIG. 31,spring 200 can bias return pin 198 such that key 199 initially abutsface 204 of trigger gear 196. After trigger 160 is released and isreturned to its unactuated position, however, D-shaped cavity 197 can berotated and aligned with key 199 such that spring 200 can bias key 199into cavity 197 as illustrated in FIG. 36. In at least one embodiment,referring to FIG. 31, when return pin 198 is slid toward trigger gear196, an end of return pin 198 can be received in slot 193 in returncarriage 194 as illustrated in FIG. 32. After key 199 has been insertedinto cavity 197, a subsequent actuation of trigger 160 can cause drivesurface 210 of D-shaped cavity 197 to abut key 199 and rotate return pin198 to a position illustrated in FIGS. 37 and 38. In effect, anactuation of trigger 160, in at least one embodiment, can rotate key 199approximately half a revolution such that key 199, which is initiallyextending substantially downwardly (FIG. 36), can be rotated such thatkey 199 is extending substantially upwardly (FIG. 37). Thereafter,trigger 160 can be released and trigger gear 194 can be rotated relativeto key 199 where key 199 can remain oriented in a substantially upwarddirection as illustrated in FIGS. 39-41.

In various embodiments, referring primarily to FIG. 38, key gear 206 canbe operably engaged with return pin 198 such that the rotation of returnpin 198 can be transmitted to key gear 206. In at least one embodiment,key gear 206 can include key-shaped aperture 212 which can be configuredto slidably receive key 199 of return pin 198. In at least one suchembodiment, key 199 can be operably engaged with both recess 197 oftrigger gear 196 and aperture 212 of key gear 206 when return pin 198 isengaged with trigger gear 196. In various alternative embodiments, keygear 206 can be fixedly mounted to return pin 198. In such embodiments,when return pin 198 is slid relative to trigger gear 196, key gear 206can also be slid relative to trigger gear 196. In various embodiments,referring generally to FIG. 38, reel 192 can include spur gear 216mounted thereto, where spur gear 216 can be operatively engaged with keygear 206 such that the rotation of key gear 206 can be transmitted toreel 192. In at least one embodiment, key gear 206, when it is slidtoward trigger gear 196 as described above, can be slid into operativeengagement with reel 192. In alternative embodiments, spur gear 216 canbe configured such that key gear 206 is in operative engagementtherewith regardless of whether key gear 206 has been biased towardtrigger gear 196.

As a result of the above, when return carriage 194 is positioned in itsactuated position illustrated in FIG. 32, an actuation of trigger 160can rotate reel 192 and wind band 190 around at least a portion thereof.In the event that key 199 cannot be operably engaged with trigger gear196 when return carriage 194 is actuated, reel 192 can be rotatedmanually to retract band 190. In at least one such embodiment, referringto FIGS. 33 and 37, bolt, or fastener, 218 can be operatively engagedwith reel 192 such that the rotation of bolt 218 can effect rotation ofreel 192. In various embodiments, a surgeon can insert bolt 218 throughan opening in surgical instrument housing 103 and engage bolt 218 withreel 192. In at least one embodiment, surgical instrument 100 canfurther include a counting mechanism (not illustrated) which can countthe actuations of trigger 160 and, in at least one such embodiment, bolt218, for example, can be operably engaged with the counting mechanism torotate reel 192. In various embodiments, as a result, the surgicalinstrument can include a first, or primary, actuator for winding reel192 and a second actuator which can be configured to wind reel 192 inlieu of the first actuator.

In various embodiments, as described above, reel 192 can be configuredto pull band 190 and retract firing member 166 and firing links 162 and164 proximally. More particularly, as described above, firing member 166and firing links 162 and 164 can be retracted relative to pawl 170 inorder to reposition firing member 166 and firing links 162 and 164 intheir starting positions. In such embodiments, especially in embodimentswhere pawl 170 is pivotable as described above, the return mechanism ofsurgical instrument 100 can be further configured to hold pawl 170 outof operative engagement with firing member 166 and firing links 162 and164 while they are moved relative to pawl 170. More particularly, whenreturn carriage 194 is moved into its actuated position illustrated inFIG. 35, return carriage 194 can be configured to contact an end offiring pin 172 and slide firing pin 172 toward pawl 170 such that firingpin 172 engages pawl 170 and prevents pawl 170 from pivoting upwardly.More particularly, referring to FIG. 34, firing pin 172 can includefirst end 220 which can include a beveled and/or rounded surface, forexample, where, when return carriage 194 contacts first end 220, returncarriage 194 can push firing pin 172 toward pawl 170. In at least oneembodiment, pawl 170 can include recess 173 which can be configured toreceive key 222 extending from firing pin 172 when firing pin 172 ismoved toward pawl 170. When key 222 and recess 173 are operativelyengaged, firing pin 172 can prevent pawl 170 from pivoting upwardly intoengagement with firing member 166 and firing links 162 and 164.

After firing member 166 and firing links 162 and 164 have beenretracted, a new staple cartridge 110 can be secured in end effector 106and surgical instrument 100 can be reset such that it can be used toincise and staple soft tissue once again. In various embodiments,referring to FIGS. 39-42, return carriage 194 can be moved from itsactuated position illustrated in FIG. 32 to its unactuated positionillustrated in FIG. 40. In at least one embodiment, return carriage 194can be rotated, or pivoted, upwardly when a force is applied to buttonportion 195. Alternatively, return carriage 194 can be moved upwardlywhen, referring to FIG. 29, trigger lock 148 is rotated upwardly todisengage follower portion 149 from closure trigger 128 in order toreopen end effector 106 as described above. More particularly, when aforce is applied to button portion 152 of trigger lock 148, trigger lock148 can be rotated upwardly such that projection 147 extending therefromcan contact return carriage 194 and move return carriage 194 upwardly aswell. In either event, referring to FIG. 42, when return carriage 194 ismoved upwardly into is unactuated position, return carriage 194 candisengage firing pin 172 from pawl 170 and, in addition, disengagereturn pin 198 from trigger gear 196. More particularly, return carriage194 can be configured to abut beveled, or rounded, end 221 of firing pin172 such that, when return carriage 194 is rotated upwardly, returncarriage 194 can slide return pin 172 away from pawl 170 and disengagekey 222 from recess 173. Similarly, when return carriage 194 is movedupwardly, a side wall of slot 193 can be configured to contact an end ofreturn pin 198 and slide return pin 198 away from trigger gear 196 todisengage key 199 from D-shaped recess 197. In short, in at least theillustrated embodiment, when button portion 152 of lock member 148 isdepressed and return carriage 194 is moved upwardly, the surgicalinstrument can be reset and can be reused once again.

Although the surgical instruments described above can be reset after thecutting member and staple driver have been completely advanced withinend effector 106, button portion 195 of return carriage 194, forexample, can be depressed after the cutting member and staple driverhave been only partially advanced within end effector 106. In variousembodiments, return carriage 194 can further include guide pin 191extending between opposite sides of return carriage 194. In at least onesuch embodiment, guide pin 191 can be slidably received within guideslot 185 (FIG. 31) in frame 184 such that slot 185 and pin 191 candefine a path for return carriage 194. In various embodiments, guide pin191 and guide slot 185 can be configured to assure that return carriage194 engages firing pin 172 and return pin 198 and resets the surgicalinstrument when return carriage 194 is moved from its actuated positionto its unactuated position as described above.

In various embodiments, surgical instrument 100 can further include abrake for preventing, or at least partially inhibiting, the firing drivefrom advancing and/or retracting the cutting member and staple driver,for example, within end effector 106. In at least one embodiment,referring to FIG. 43, frame 184 can include brake surface 187 wherebrake surface 187 can be configured to apply a braking force to band190. More particularly, when band 190 is pulled proximally and/ordistally as described above, frame 184 can be configured such that band190 slides over brake surface 187 and a friction force is createdtherebetween. In various embodiments, referring to FIG. 44, brakesurface 187′ can be configured such that the path of band 190 betweenfiring member 166 and reel 192 is interrupted by brake surface 187′ anda significant normal force can be applied to band 190.

In at least one embodiment, band 190 can be engaged with brake surface187′ when band 190 is at rest such that a static friction force betweenband 190 and brake surface 187′ can prevent, at least initially, band190 from moving relative to brake surface 187′ when a pulling force isapplied to band 190. When the pulling force applied to band 190 exceedsthe static friction force, band 190 can be moved relative to brakesurface 187′. Such embodiments may be particularly useful when trigger160 is actuated more than one time to advance the cutting member and/orstaple driver within end effector 106. More particularly, after anactuation of trigger 160, pawl 170 can be retracted relative to firingmember 166 as described above and, in various embodiments, the frictionforce between band 190 and brake surface 187′ can prevent, or at leastpartially inhibit, firing member 166 and/or firing links 162 and 164from moving proximally, and/or distally, as pawl 170 is retracted. As aresult of the above, the alignment between tooth 174 of pawl 170 and therecesses in firing member 166 and firing links 162 and 164 can bemaintained when pawl 170 is moved relative thereto.

Similarly, in at least one embodiment, the stiffness of band 190 canalso assist in holding firing member 166 and firing links 162 and 164 inposition. More particularly, in order for firing member 166 to ‘backup’, or move proximally, firing member 166 would have to push band 190proximally and, in effect, wind band 190 around reel 192. In variousembodiments, the stiffness of band 190 can be such that a significantforce to wind band 190 around reel 192 is required and, as a result,firing member 166 can be held in place. To further increase the forcerequired to wind band 190 around reel 192, referring to FIG. 44, thepath of band 190 can be controlled such that is not wound onto reel 192in a tangential direction. More particularly, if the path of band 190 issuch that it is wound onto reel 192 in a non-tangential direction, aportion of the force transmitted through band 190 will be lost thusresulting in a poor mechanical advantage for winding reel 192.

In various embodiments, surgical instrument 100 can include a brakewhich can be engaged with reel 192, or any other suitable component ofthe firing drive, to prevent firing member 166 and/or firing links 162and 164 from being retracted unintentionally, for example. In at leastone embodiment, although not illustrated, the brake can be moved betweena first position and a second position, where, when the brake is in thefirst position, the brake can apply a first braking force to band 190,for example. In at least one such embodiment, the brake can apply, whenit is in the second position, a second braking force to band 190, forexample, which can be greater than or less than the first braking force.In various alternative embodiments, the brake may not be engaged withband 190 or any other portion of the firing drive when the brake is inthe second position. In various embodiments, although not illustrated,surgical instrument 100 can include a detent mechanism which can apply abraking force to reel 192 and/or band 190. In at least one suchembodiment, the detent mechanism can include a ball detent and a springmember for biasingly engaging the ball detent against reel 192 and/orband 190.

In various embodiments, surgical instrument 100 can include a ratchetwhich can allow reel 192 to turn in a first direction but can, invarious circumstances, prevent reel 192 from turning in a directionopposite the first direction. In at least one embodiment, referring toFIGS. 45-49, surgical instrument 100 can include ratchet assembly 230,where ratchet assembly 230 can include ratchet wheel 232 and ratchetpawl 234. In various embodiments, ratchet wheel 232 can operate insubstantially the same way as key gear 206 described above except that,referring primarily to FIGS. 47 and 48, ratchet wheel 232 can includeratchet teeth 236 which can, owing to a ratcheting engagement withratchet pawl 234, prevent ratchet wheel 232 from being turned in aclockwise direction, for example, when return carriage 194′ is in itsunactuated position (FIG. 47). More particularly, each ratchet tooth 236can include a flat surface 240 where, referring to FIG. 48, at least oneof flat surfaces 240 can abut edge 235 of pawl 234 and thereby preventratchet wheel 232 from being rotated in a clockwise direction.

Each ratchet tooth 236 can further include an inclined surface 238,where inclined surfaces 238 can be configured to slide underneath pawl234 when ratchet wheel 232 is turned in a counter-clockwise direction.As a result of the above, ratchet assembly 230 can allow band 190 to bepulled distally by firing member 166, for example, but prevent, or atleast substantially inhibit, band 190 from being moved proximally, atleast when return carriage 194′ is in its unactuated position. Whenreturn carriage 194′ is pivoted downwardly into its actuated position,as described above with regard to return carriage 194, ratchet wheel 232can be slid toward trigger gear 196′ and out of operative engagementwith ratchet pawl 234. Thereafter, as a result, ratchet wheel 232 can berotated in either a clockwise or counter-clockwise direction withoutinterference, or at least substantial interference, from ratchet pawl234. In various alternative embodiments where ratchet wheel 232 is notslid toward trigger gear 196′, ratchet pawl 234 can be moved downwardlyand out of operative engagement with ratchet teeth 236 when returncarriage 194′ is moved into its actuated position. In either event, whenreturn carriage 194′ is in its actuated position, trigger gear 196′ andreturn pin 198′ can rotate ratchet wheel 232 and cam 192′ to retractband 190 and firing member 166.

In various embodiments, referring to FIGS. 68-86, surgical instrument400 can include a closure system for closing the anvil of an endeffector, a firing drive for advancing a firing rod, cutting member,and/or staple driver within the end effector, and a gear-drivenreversing drive for retracting at least one of the firing rod, cuttingmember, and/or staple driver relative to the end effector. In at leastone embodiment, referring to FIG. 68, the closure system can includeclosure trigger 428, drive link 130, and driver 132 where, similar tothe above, closure trigger 428 can be configured to displace drive link130 and driver 132 when closure trigger 428 is moved from its unactuatedposition illustrated in FIG. 68 to its actuated position illustrated inFIG. 69. In various embodiments, the actuation of closure trigger 428can unlock the firing drive. In at least one embodiment, the firingdrive can include firing trigger 460 which, when closure trigger 428 isrotated toward handle 427, can be moved between a locked positionillustrated in FIG. 68 and an unlocked position illustrated in FIG. 69.In at least one such embodiment, closure trigger 428 can include slot,or groove, 128 a which can receive pin, or projection, 160 a extendingfrom firing trigger 460, wherein a sidewall of slot 128 a can beconfigured to prevent pin 160 a, and firing trigger 460, from moving, orat least substantially moving, relative to closure trigger 428 whenclosure trigger 428 is in its unactuated position (FIG. 68). Whenclosure trigger 428 is actuated, or closed, the side wall of slot 128 acan abut pin 160 a and move firing trigger 460 between its lockedposition illustrated in FIG. 68 and its unlocked position illustrated inFIG. 69. In such an unlocked position, slot 128 a can be oriented topermit pin 160 a to move within slot 128 a thereby allowing firingtrigger 460 to move relative to closure trigger 428 and advance thefiring drive as described in greater detail below.

In various embodiments, referring to FIG. 68, the firing drive cancomprise firing trigger 460, firing pin 172, and pawl 170, whereinfiring trigger 460 can be operably engaged with firing rod, or member,466 via pawl 170 and firing pin 172 in order to advance the cuttingmember and the staple driver within the end effector. In at least onesuch embodiment, similar to the above, pawl 170 can be pivoted upwardlyinto engagement with firing member 466 such that, when firing trigger460 is actuated, referring to FIG. 70, firing trigger 460 can advancefiring pin 172, pawl 170, and firing member 466 distally. Thereafter,referring to FIG. 101, pawl 170 can be pivoted downwardly out ofengagement with firing member 466 such that pawl 170 can be retractedproximally relative to firing member 466 when firing trigger 460 isreleased or returned to its unactuated, and unlocked, positionillustrated in FIG. 72. Upon comparing FIGS. 69 and 72, it is readilyapparent that a first cycle of the firing drive has moved firing member466 distally and has also repositioned pawl 170, firing pin 172, andfiring trigger 460 such that firing trigger 460 can be actuated a secondtime to further advance firing member 466. In such circumstances,referring to FIG. 102, pawl 170 can be pivoted upwardly into operativeengagement with firing member 466 and advanced distally by actuatingfiring trigger 460 once again.

In various embodiments, referring to FIGS. 101 and 102, firing member466 can include a plurality of recesses 467 which can each receive atleast a portion of pawl 170 such that pawl 170 can serially engage therecesses 467 in order to advance firing member 466 a plurality of timesas described above. More particularly, in at least one embodiment,firing member 466 can include three recesses 467 which can allow firingmember 466 to be advanced at least three times by trigger 460. By way ofexample, FIG. 73 illustrates the firing drive upon a second actuation oftrigger 460, FIG. 74 illustrates the firing drive after trigger 460 hasbeen returned to its unactuated position after its second actuation,FIG. 75 illustrates the firing drive upon a third actuation of trigger460, and FIG. 82 illustrates the firing drive after trigger 460 has beenreturned to its unactuated position after its third actuation. At suchpoint, as described in greater detail below, the firing drive can bedisengaged from firing member 466 and the reversing drive can beoperably engaged with firing member 466 such that, in variousembodiments, firing member 466 can be retracted relative to the endeffector and the surgical instrument can be reset. Although firingtrigger 460 is actuated three times in order to fully advance firingmember 466 in the illustrated exemplary embodiment, other embodimentsare envisioned which can utilize more than, or less than, three strokesor actuations of the firing trigger.

In various embodiments, as outlined above, surgical instrument 400 canfurther include a gear-driven reversing drive, or mechanism, which canbe configured to retract firing member 466, the cutting member, and/orthe staple driver relative to the end effector of the surgicalinstrument. In at least one embodiment, the reversing mechanism can beoperably engaged with firing member 466, or any other suitable portionof the firing drive, to move firing member 466 proximally. In at leastone such embodiment, referring to FIG. 71, the reversing drive caninclude a gear train comprising trigger gear 496, key gear 406, piniongear 401, intermediate gear 403, and spur gear 416, for example. Invarious embodiments, referring to FIG. 84, the reversing drive canfurther include gear portion 158 extending from firing trigger 460 whichcan be configured such that, when firing trigger 460 is rotated aboutpin 161, similar to the above, gear portion 158 can rotate trigger gear496 about an axis defined by return pin 498. In at least one embodiment,gear portion 158 and trigger gear 496 can include teeth and/or recesseswhich can be configured to cooperate and transmit rotational motiontherebetween.

Referring to FIG. 77, also similar to the above, trigger gear 496 andreturn pin 498 can be configured such that they can be selectivelyengaged and disengaged with one another. In at least one suchembodiment, trigger gear 496 can be operably disengaged with return pin498 when firing member 466 is advanced by the firing drive. Statedanother way, trigger gear 496 can be configured such that it does nottransmit, or at least substantially transmit, rotational motion toreturn pin 498 when firing member 466 is being advanced by the firingdrive as described above. Furthermore, in at least one such embodiment,referring to FIGS. 77 and 79, return pin 498 can include key 499extending therefrom wherein key 499 can be held out of operativeengagement with D-shaped cavity 497 in trigger gear 496 until thereversing drive is operatively engaged with firing member 466 asdescribed in greater detail below. In order to hold key 499 out ofoperative engagement with trigger gear 496, referring to FIG. 84, returnpin 498 can include end 498 a which can be displaced, and/or held inposition, by return carriage 494 such that key 499 is positioned outsideof D-shaped cavity 497.

Before trigger gear 496 and return pin 498 are operatively engaged asmentioned above, pinion gear 401 of the reversing drive, referring toFIG. 71, can be operatively engaged with rack portion 405 of firingmember 466 such that, when firing member 466 is advanced distally by thefiring drive as described above, rack portion 405 can rotate pinion gear401 about an axis defined by axle 407. In various embodiments, rack 405can include a plurality of teeth and/or grooves which can be configuredto convert translational movement of firing member 466 into rotationalmovement of pinion gear 401. In various embodiments, intermediate gear403 can be mounted to or integrally formed with pinion gear 401 suchthat the translation of firing member 466 can rotate intermediate gear403 as well. In at least one embodiment, intermediate gear 403 and keygear 406 can include teeth and/or recesses which can be configured tocooperate and transmit rotational motion therebetween. Similarly, spurgear 416 can include teeth and/or recesses which can be configured tocooperate with the teeth and/or recesses of key gear 406 and transmitrotational motion therebetween. Thus, in view of the above, theadvancement of firing member 466 can rotate gears 401, 403, 406, and 416of the gear train.

In at least one embodiment, referring to FIGS. 71 and 84, spur gear 416can be mounted to or integrally-formed with indicator gear 492 suchthat, when spur gear 416 is rotated by key gear 406 as outlined above,indicator gear 492 can be rotated by spur gear 416. Thus, in at leastone such embodiment, the forward advancement of firing member 466 canrotate indicator gear 492 about an axis defined by aperture 407. Invarious embodiments, indicator gear 492 can include at least oneindicium thereon, such as letters, numbers, and/or any other suitablesymbols, for example, for displaying the number of times that firingtrigger 460 has been actuated, for example. In at least one suchembodiment, the housing of the surgical instrument can include a windowor aperture therein wherein a numeral “1”, for example, on indicatorgear 492 can be aligned with the window after a first actuation offiring trigger 460. Similarly, a numeral “2”, for example, on indicatorgear 492 can be aligned with the window after a second actuation offiring trigger and, correspondingly, a numeral “3”, for example, can bealigned with the window after a third actuation. Alternatively, in atleast one embodiment, indicator gear 492 can include indicia thereonwhich can correspond to the number of remaining actuations which arenecessary to fully advance firing member 466, the cutting member, and/orthe staple driver relative to the end effector.

After firing member 466 has been fully advanced relative to the endeffector, or at least suitably advanced, return carriage 494 can berotated downwardly, referring to FIGS. 76 and 82, in order to operablycouple the reversing drive, firing trigger 460, and firing member 466.In various embodiments, return carriage 494 can be rotated about pin 494a such that return carriage 494 no longer contacts, or at leastsubstantially contacts, return pin 498. Thereafter, referring to FIGS.77 and 78, spring 400 can slide or displace return pin 498 towardtrigger gear 496 and position at least a portion of key 499 withincavity 497. In at least one such embodiment, referring to FIG. 78,spring 400 can be positioned intermediate frame 484 and key 499 ofreturn pin 498 such that, when return carriage 494 no longer contactsend 498 a, spring 400 can expand and displace key 499 into cavity 497.In various embodiments, referring to FIG. 80, return carriage 494 canalso operably disengage the firing drive from firing member 466 whenreturn carriage 494 is rotated downwardly as described above. Moreparticularly, referring to FIG. 81, return carriage 494 can contact end220 of firing pin 172 such that firing pin 172 can be slid toward pawl170 and, as also described above, firing pin 172 can include key 222extending therefrom which can engage recess 173 in pawl 170 to preventpawl 170 from being pivoted upwardly to engage firing member 466. Thus,when pawl 170 is prevented from operably engaging firing member 466, thefiring drive may no longer engage firing member 466 and the reversingdrive can retract firing member 466 without interference from the firingdrive.

Further to the above, in various embodiments, return carriage 494 can berotated downwardly manually by a surgeon or by another clinician, forexample. In various embodiments, referring generally to FIGS. 68 and 82,the surgeon can apply a force to button portion 495 such that returncarriage 494 can be pivoted downwardly about an axis defined by pin 494a. Such a force can be applied after a predetermined amount ofactuations of the firing trigger although, in various embodiments, sucha force can be applied before the predetermined amount of actuations ofthe firing trigger is reached. In addition to or in lieu of the above,at least one of the gears of the reversing mechanism can be configuredto contact return carriage 494 after a predetermined number ofactuations of firing trigger 460. In various embodiments, referring toFIG. 76, indicator gear 492 can include cam 402 which can be configuredto contact a portion of return carriage 494 and apply a force theretoupon the third actuation of firing trigger 460. In at least one suchembodiment, the advancement of firing member 466 can rotate indicatorgear 492 a predetermined amount upon each actuation of trigger 460 suchthat cam 402 can contact carriage 494 upon the third, or final, strokeof trigger 460 which advances firing member 466. In effect, indicatorgear 492, or any other suitable gear of the reversing mechanism, can beconfigured to be rotated a predetermined amount before switching thesurgical instrument from an ‘advancing’ operating mode to a ‘reversing’operating mode.

Once return pin 498 has been operably engaged with trigger gear 496 andfiring pin 172 has been engaged with pawl 170 in order to prevent pawl170 from operably engaging firing member 466 as described above, firingtrigger 460 can be actuated once again in order to retract firing member466. In at least one such embodiment, the subsequent actuation of firingtrigger 466 can rotate trigger gear 492 and, owing to the operativeengagement between trigger gear 492 and return pin 498, trigger gear 492can rotate key gear 406. More particularly, referring to FIGS. 71, 77,and 78, return pin key 499 can be operatively engaged with drive surface410 of trigger gear 492 in addition to a sidewall of cavity 406 a withinkey gear 406 such that the rotation of trigger gear 496 is transmittedto key gear 406 via return pin 498. In various embodiments, referringagain to FIG. 71, the rotation of key gear 406 can rotate intermediategear 403 and pinion gear 401 in order to drive, or retract, firingmember 466 proximally. In effect, when trigger 460 is operably engagedwith the reversing drive, pinion gear 401 can be rotated in a directionwhich is opposite the direction in which it is rotated when firingtrigger 460 is operably engaged with the firing drive. In variousembodiments, the size, or pitch radius, of gears 401, 403, 406, 492, 496and gear portion 158 of trigger gear 460, for example, can be selectedsuch that firing member 466 can be returned by one actuation of trigger460, although other embodiments are envisioned in which more or lessthan one actuation of trigger 460 can be utilized.

After firing member 466 has been retracted, return carriage 494 can bepivoted upwardly into it its unactuated position in order to reset thesurgical instrument. In various embodiments, referring to FIGS. 85 and86, the surgeon or clinician can apply a force to button portion 452 oftrigger lock 448 such that trigger lock 448 can rotate upwardly and abutreturn carriage 494. In such circumstances, trigger lock 448 can rotatereturn carriage 494 upwardly as well and position carriage 494 in itsunactuated position. In doing so, return carriage 494 can engage end 221of firing pin 172 in order to slide firing pin 172 away from pawl 170and disengage key 222 from recess 173 in pawl 170 thereby allowing pawl170 to re-engage firing member 466 upon a subsequent actuation of firingtrigger 460. Return carriage 494 can also re-engage end 498 a of returnpin 498 when it is rotated upwardly so as to slide key 499 away fromtrigger gear 496, thereby operably disengaging return pin 498 fromtrigger gear 496 and, correspondingly, operably disengaging thereversing drive from firing member 466. Thereafter, the spent staplecartridge can be detached from the surgical instrument and replaced witha new staple cartridge such that the surgical instrument can be usedonce again.

In various alternative embodiments, a surgical instrument can include aclutch configured to operably engage and disengage a reversing drivewith a firing member. In at least one embodiment, referring to FIGS.87-94, surgical instrument 500, similar to surgical instrument 400, caninclude firing trigger 560 which can be configured to drive a firing pinand a pawl of a firing drive, for example, so as to advance firingmember 566, a cutting member, and/or staple driver relative to an endeffector. In various embodiments, also similar to the above, thesurgical instrument can further include a reversing drive comprisingpinion gear 501, intermediate gear 503, key gear 506, and spur gear 516.In at least one such embodiment, owing to the operative engagementbetween rack portion 505 of firing member 496 and pinion gear 501, theadvancement of firing member 466 can rotate gears 501, 503, 506 and 516as described in greater detail below. In various embodiments, return, orkey, pin 598 can be mounted to or integrally formed with key gear 506such that rotational motion is transmitted therebetween. In at least onesuch embodiment, referring to FIG. 89, at least a portion of return pin598 can include a non-circular cross-section including flat portion 598b, for example, which can, referring to FIG. 92, be slidingly receivedwithin a correspondingly-shaped aperture 506 b in key gear 506. Alsosimilar to the above, firing trigger 560 can include gear portion 558which can be operatively engaged with trigger gear 596 such that gearportion 558 can rotate trigger gear 596 about an axis defined by key pin598, as described in greater detail below.

In use, upon the first actuation of firing trigger 560, firing trigger560 can, similar to the above, rotate trigger gear 596 about key pin 598without directly transmitting rotational movement to key pin 598 viatrigger gear 596. Referring to FIG. 88, the first actuation of firingtrigger 560 can rotate trigger gear 596 in a direction indicated byarrow “A”, i.e., clockwise for the purposes of this discussion. Alsoupon the first actuation of firing trigger 560, firing member 566 canrotate pinion gear 501 and intermediate gear 503 in a directionindicated by arrow “B”, key gear 506 in a direction indicated by arrow“C”, and spur gear 516 and indicator gear 592 in a direction indicatedby arrow “D”. In various embodiments, as illustrated in FIG. 88, triggergear 596 and key gear 506 can be rotated in opposite directions duringthe first actuation of trigger 560 and may not operably engaged witheach other until after the first actuation of trigger 560 as describedfurther below. When trigger 560 is released or returned to itsunactuated position after its first actuation, the pawl of the firingdrive, for example, can be disengaged from the firing member 566 suchthat pinion gear 501 and key gear 506, for example, are not rotated, orat least substantially rotated, when trigger 560 is returned to itsstarting, or unactuated, position. Trigger gear 596, however, can berotated by firing trigger 560 when trigger 560 is returned to itsunactuated position and, as a result, trigger gear 596 can be rotatedrelative to key gear 506 as illustrated in FIG. 89. As trigger 560 isreturned to its unactuated position, as described above, inclinedsurface 509 of trigger gear 596 can contact clutch dog 599 of key pin598 and displace key pin 598 away from trigger gear 596 as illustratedin FIG. 90. Thereafter, trigger gear 596 can be further rotated byfiring trigger 560 until inclined surface 509 has entirely passed byclutch dog 599 and spring 500 can bias clutch dog 599 into a positionbehind drive surface 510 as illustrated in FIG. 91. At such point,firing trigger 560 may be in its unactuated position.

Upon a second actuation of firing trigger 560, the pawl of the firingdrive can remain disengaged from firing member 566 although the secondactuation of firing trigger 560 can once again rotate trigger gear 596in a direction indicated by arrow A, referring to FIG. 92. Owing to theposition of dog 599 behind drive surface 510 of trigger gear 596, therotation of trigger gear 596 can cause key pin 598 and key gear 506 torotate in a clockwise direction indicated by arrow A as well, i.e., in adirection opposite of arrow C. Correspondingly, key gear 506 can rotatepinion gear 501 and intermediate gear 503 in a direction indicated byarrow E, i.e., a direction opposite of arrow B, and also rotateindicator gear 592 in a direction indicted by arrow F, i.e., a directionopposite of arrow D. Owing to the rotation of pinion gear 501 in anopposite direction during the second actuation of trigger 560, piniongear 501 can retract firing member 566 relative to the end effector andreposition, or at least substantially reposition, firing member 566 inits starting, or unactuated, position. Thereafter, firing trigger 566can be released and returned to its unactuated position. In suchcircumstances, drive surface 510 of trigger gear 596 can be rotated awayfrom clutch dog 599 and, whereas the pawl of the firing drive can stillbe operatively disengaged from firing member 566, key pin 598 and keygear 596 can remain in position. In order to reset the surgicalinstrument, the pawl of the firing drive can be released such that itcan re-engage firing member 566 upon the next actuation of trigger 560.In such embodiments, the spent staple cartridge can be replaced suchthat the surgical instrument can be used once again.

In various embodiments, referring to FIG. 94, surgical instrument 500can further include trigger lock 548 which, similar to trigger lock 148described above, can be utilized to hold a closure trigger in position.In at least one embodiment, trigger lock 548 can be rotated betweenactuated and unactuated positions to lock and unlock, respectively, aclosure trigger such as closure trigger 428 (FIG. 68), for example. Inat least one such embodiment, when trigger lock 548 is in its unactuatedposition, portion 548 a of trigger lock 548 can be positioned withinrecess 592 a of indicator 592 to prevent, or at least substantiallyprevent, the gear train and firing member 566 from being unintentionallymotivated. Stated another way, when portion 548 a is positioned withinrecess 592 a, the firing and reversing drives described above can berendered substantially inoperative and, as a result, firing member 566cannot be substantially moved. When trigger lock 548 is moved into itsactuated position to hold or lock the closure trigger in place, portion548 a of trigger lock 548 can be moved, or rotated, out of recess 592 asuch that the firing and reversing drives described above can beoperated.

In various alternative embodiments, a surgical instrument can include aratchet configured to operably engage and disengage a reversing drivewith a firing member. In at least one embodiment, referring to FIGS.95-100, surgical instrument 600 can include firing trigger 660 which canbe configured to drive a firing pin and a pawl of a firing drive, forexample, so as to advance firing member 666, a cutting member, and/orstaple driver relative to an end effector, similar to the above. Invarious embodiments, also similar to the above, the surgical instrumentcan further include a reversing mechanism comprising pinion gear 601,key gear 606, and spur gear 616 where the advancement of firing member666 can rotate gears 601, 606 and 616 owing to the operative engagementbetween rack portion 605 of firing member 696 and pinion gear 601. Invarious embodiments, return, or key, pin 698 can be mounted to orintegrally formed with key gear 606 such that rotational motion can betransmitted therebetween. Also similar to the above, firing trigger 660can include gear portion 658 which can be operatively engaged withtrigger gear 696 such that gear portion 658 can rotate trigger gear 696about an axis defined by key pin 698.

In use, upon the first actuation of firing trigger 660, firing trigger660 can rotate trigger gear 696 about key pin 698 without directlytransmitting rotational movement to key pin 698 and key gear 606. Moreparticularly, referring to FIG. 97, trigger gear 696 can includeaperture 696 a which can be configured such that there is a clearancefit between key pin 698 and the sidewalls of aperture 696 a and, as aresult, key pin 698 can rotate therein. Furthermore, referring to FIG.96, key gear 606 can include ratchet face 606 c and trigger gear 696 caninclude ratchet face 696 c which, when firing member 666 is beingadvanced by the firing drive, can be operably disengaged, or separated,from one another such that rotational movement is also not transmittedtherebetween. After firing member 666 has been sufficiently advanced,similar to the above, return carriage 694 can be rotated downwardlyabout pin 694 a, for example, such that return carriage 694, referringto FIG. 99, can be disengaged from end 698 a of return pin 698. In suchcircumstances, as described in greater detail below, return pin 698 canbe operatively engaged with trigger gear 696 and firing member 666 canbe retracted.

In various embodiments, further to the above, return carriage 694 can bemanually moved between its unactuated position illustrated in FIG. 95 toits actuated position illustrated in FIG. 99, similar to return carriage494. In addition to or in lieu of the above, at least one of the gearsin the gear train, such as indicator gear 692, for example, can includea cam, such as cam 602, for example, which can contact return carriage694 and rotate it downwardly after a predetermined amount of actuationsof firing trigger 660. Thereafter, in either event, key gear 606 can beslid toward trigger gear 696 by spring 600. More particularly, referringto FIG. 100, spring 600, which can be positioned, or compressed,intermediate key gear 606 and a frame of the surgical instrument, forexample, such that, once return carriage 694 has been disengaged fromend 698 a of return pin 698, spring 600 can expand to slide key gear 606toward trigger gear 696. Furthermore, in at least one embodiment, returnpin 698 can be mounted to or integrally formed with key gear 606 suchthat return pin 698 can be slid toward trigger gear 696 with key gear606. In at least one embodiment, referring to FIG. 97, return pin 698can include collar 698 b in which key gear 606 can abut and push returnpin 698 toward trigger gear 696.

In various embodiments, as a result of the above, ratchet faces 606 cand 696 c can be positioned against one another by spring 600 whenreturn carriage 694 is rotated downwardly into its actuated position asillustrated in FIG. 100. In at least one embodiment, referring to FIG.97, ratchet faces 606 c and 696 c can each include teeth extendingtherefrom which can cooperate to transmit rotational movementtherebetween. In use, upon a subsequent actuation of firing trigger 660,firing trigger 660 can rotate trigger gear 696, and key gear 606, in aclockwise direction indicated by arrow A, referring to FIG. 99, whereinkey gear 606 can rotate pinion gear 601 in a direction indicated byarrow E. As a result of the operative engagement between pinion gear 601and rack portion 605 of firing member 666, for example, pinion gear 601can retract firing member 666, the cutting member, and/or the stapledriver relative to the end effector, similar to the above. In at leastone embodiment, gears 601, 606, and 696 and gear portion 658 can beconfigured such that firing member 666 can be fully retracted with oneactuation of trigger 460.

Thereafter, firing trigger 460 can be released and/or returned to itsunactuated position. In at least one such embodiment, ratchet faces 606c and 696 c can include beveled surfaces which can allow ratchet faces606 c and 696 c to rotate relative thereto when trigger 660 is returnedto its unactuated position. In such circumstances, trigger gear 696 canbe rotated in a counterclockwise direction, i.e., in a directionopposite of that indicated by arrow A. In at least one embodiment,ratchet faces 606 c and 696 c can rotate relative to each othereventhough the ratchet faces are in contact with one another.Thereafter, return carriage 694 can be rotated upwardly such that it cancontact end 698 a of return pin 698 and slide return pin 698 and keygear 606 away from trigger gear 696. In such circumstances, as a result,ratchet face 606 c can be disengaged from ratchet face 696 c such thatthey are no longer operably engaged with one another. In at least onesuch embodiment, return carriage 694 can apply a force to end 698 a ofreturn pin 698, wherein the force can be transmitted to key gear 606 viacollar 698 b in order to displace key gear 606 away from trigger gear696.

As described above, surgical instruments in accordance with the presentinvention can include a firing drive having a pawl which can beconfigured to advance a firing member relative to an end effector. Invarious embodiments, as described above, pawl 170 can be pivotedupwardly to engage a recess 467 in firing member 466, for example, andadvance firing member 466 distally. Thereafter, referring once again toFIGS. 101 and 102, pawl 170 can be pivoted downwardly and retractedproximally relative to firing member 466 so as to reposition pawl 170such that pawl 170 can be pivoted upwardly once again to engage anotherrecess 467 and further advance firing member 466. In variouscircumstances, though, pawl 170 may not be able to engage a recess 467when it is pivoted upwardly as illustrated in FIG. 103. Suchcircumstances may arise when firing member 466, for example, isunintentionally moved by forces or energy transmitted through and/orstored within the various mechanisms of the surgical instrument. If thepawl is unable to re-engage the firing member, the surgical instrumentmay be rendered inoperable and, as a result, the surgical instrument mayhave to be manually reset. In order to ameliorate this condition,surgical instruments in accordance with various embodiments of thepresent invention can include an anti-backup mechanism which can retain,or at least substantially retain, the firing member in position.

In various embodiments, referring to FIG. 104, an anti-backup mechanismcan be configured to hold at least a portion of a firing drive and/orreversing drive in position while pawl 170 is retracted relative tofiring member 466, for example. In at least one embodiment, ananti-backup mechanism can include indexing mechanism, or plate, 711which can be configured to permit return pin 798 to rotate in acounter-clockwise direction indicated by arrow B when firing member 466is advanced, as described above, yet prohibit, or at least substantiallyprohibit, return pin 798 from rotating in a clockwise direction, i.e.,in a direction opposite of arrow B. In effect, as return pin 798 isrotatably engaged with key gear 406, and key gear 406 is operablyengaged with firing member 466 via intermediate gear 403 and pinion gear401, indexing mechanism 711 can also prevent, or at least substantiallyprevent, firing member 466 from being retracted proximally. Furthermore,as described in greater detail below, indexing mechanism 711 can alsoinhibit firing member 466 from being unintentionally advanced distallyas well.

In order to prevent return pin 798 from unintentionally rotating asoutlined above, indexing element 711 can include one or more recessesand/or apertures therein for holding or retaining return pin 798 inposition. In various embodiments, referring to FIGS. 104, 107, and 111,indexing mechanism 711 can comprise a leaf spring including clip end 711a which can be retained within recess 784 a of frame 784 such thatindexing mechanism 711 can flex and/or rotate relative to fulcrum 784 bof frame 784. In at least one embodiment, referring to FIGS. 105 and106, return pin 798 can include key 799 extending therefrom wherein key799 can be configured to engage indexing mechanism 711. Moreparticularly, in at least one such embodiment, indexing mechanism 711can include a plurality of recesses, or apertures, 713 a-d, referring toFIGS. 107 and 108, which can each be configured to retain projection 799a extending from key 799 therein and thereby hold return pin 798 inposition as described in greater detail below.

In use, an end effector of the surgical instrument can be closed ontothe soft tissue of a patient, for example and, thereafter, as outlinedabove, a firing member of the surgical instrument can be advanced by afiring drive. Prior to the advancement of the firing member, projection799 a of return pin 798 can be received within first aperture 713 a ofindexing element 711 as illustrated in FIG. 110 a. In variousembodiments, referring to FIGS. 106 and 109, key 799 can further includeinclined or beveled surface 799 b which can be configured such that,when return pin 798 is rotated in a direction indicated by arrow B byfiring member 466, pinion gear 401, intermediate gear 403, and key gear406 upon the first actuation of trigger 460, beveled surface 799 b cancontact the edge of aperture 713 a and deflect and/or rotate indexingmechanism 711 downwardly as illustrated in FIG. 110 b. Notably, acertain amount of force may be required to deflect and/or rotateindexing mechanism 711 and, as a result, the possibility of return pin798 being unintentionally displaced from recesses 713 can be reduced.More particularly, absent a large pulling force applied to firing member766, for example, the recesses in the indexing element may be able tohold key 799 of return pin 798 therein and, correspondingly, thepossibility that firing member 466 may be unintentionally advanced canalso be reduced.

By the end of the first actuation of firing trigger 460, key 799 can bepositioned within second aperture 713 b of indexing mechanism 711 asillustrated in FIG. 110 c. In such a position, key 799 can be preventedfrom moving backward into aperture 713 a owing to stop surface 799 c.More particularly, referring to FIG. 108, key 799 can further includestop surface 799 c which can be configured to abut the perimeter ofaperture 713 b, for example, and, owing to the configuration of stopsurface 799 c, aperture 713 b and stop surface 799 c can be configuredto prevent key 799 from deflecting or rotating indexing mechanism 711downwardly within recess 715 (FIG. 111) and allowing return pin 798 tobe rotated in a direction opposite of arrow B. In at least one suchembodiment, stop surface 799 c and the perimeter of aperture 713 b caninclude surfaces which are parallel to one another. In other variousembodiments, the abutting surfaces can include at least partiallybeveled portions which can be configured such that, when stop surface799 c is forced against the edge of aperture 713 b, key 799 can befurther drawn into aperture 713 b as opposed to being lifted out of thesame. In either event, owing to the operative relationship betweenreturn pin 798, the gears of the gear train, and firing member 466 asdescribed above, firing member 466 can be prevented, or at leastsubstantially prevented, from unintentionally retracting proximally byindexing member 711. In such embodiments, as a result, the possibilitythat pawl 170 may be misaligned relative to the recesses 467 withinfiring member 466 when pawl 170 is retracted relative to firing member466, for example, can be reduced.

Upon a second actuation of firing trigger 460, firing member 466 canonce again rotate gears 401, 403, and 406 such that return pin 798 isrotated in a direction indicated by arrow B. In various embodiments, asa result, beveled surface 799 b can contact the edge of second aperture713 b and deflect and/or rotate indexing mechanism 711 downwardly asillustrated in FIG. 110 d. By the end of the second actuation of firingtrigger 460, key 799 can be positioned within third aperture 713 c ofindexing mechanism 711 as illustrated in FIG. 110 e. In such a position,key 799 can be prevented from moving backward into second aperture 713 bowing to stop surface 799 c, similar to the above. Furthermore, upon athird actuation of firing trigger 460, firing member 466 can once againrotate return pin 798 in a direction indicated by arrow B and, as aresult, beveled surface 799 b can contact the edge of third aperture 713c and deflect and/or rotate indexing mechanism 711 downwardly asillustrated in FIG. 110 f. By the end of the third actuation of firingtrigger 460, key 799 can be positioned within fourth aperture 713 d ofindexing mechanism 711 as illustrated in FIG. 110 g. In such a position,similar to the above, key 799 can be prevented from moving backward intothird aperture 713 c owing to stop surface 799 c.

At such point, in order to operably engage the reversing drive with thefiring member, similar to the above, return pin 798 and key 799 can bemoved toward trigger gear 496 in order to operably engage key gear 406with trigger gear 496. In various embodiments, as a result, projection799 a can be moved away from indexing member 711 and out of fourthaperture 713 d. Thereafter, upon the return stroke of firing trigger460, firing member 466 can be retracted and return pin 798 can berotated in a clockwise direction, i.e., in a direction opposite arrow B.At such point, firing member 466 and pawl 170 will have both beenreturned to their staring positions, return pin 798 will have beenrotated such that it is realigned with first aperture 713 a, and returnpin 798 can be disengaged from trigger gear 496 such that key 499 isslid into engagement with first aperture 713 a. Thereafter, as a result,the surgical instrument can be used once again.

In various alternative embodiments, referring to FIGS. 112 and 113, ananti-backup mechanism can include indexing element, or plate, 811 whichcan be rotatably mounted within recess 884 a of frame 884 such thathinge end 811 a can be rotatably mounted to pin portion 884 b. In atleast one embodiment, similar to the above, indexing element 811 can berotated and/or deflected relative to pin 811 b. In various embodiments,the anti-backup mechanism can further include at least one springelement, or return spring, 811 b within recess 815 which can beconfigured to bias indexing member 811 into the position illustrated inFIGS. 112 and 113. Similarly, return spring 811 b can be furtherconfigured to restore indexing element to such a position after it hasbeen deflected by key 799 as outlined above. In various embodiments, theat least one return spring can be positioned intermediate indexingelement 811 and a sidewall of recess 815, for example. In variousalternative embodiments, referring to FIG. 114, an anti-backup mechanismcan include indexing element 911 which, similar to the above, can bemounted within recess 984 a of frame 984. In at least one suchembodiment, frame 984 can further include mounting projections 984 bwhich can be configured to be press-fit within apertures 911 a inindexing element 911 such that indexing element 911 can be flexed and/orrotated relative to frame 984.

In various alternative embodiments, an anti-backup mechanism inaccordance with at least one embodiment of the present invention caninclude a ratchet mechanism for preventing, or at least limiting,undesirable movement of the firing member and/or gear train. In variousembodiments, referring to FIGS. 115-118, the ratchet mechanism caninclude a pawl which can be configured to allow the gears of the geartrain, such as indicator gear 492 and spur gear 416, for example, torotate in a first direction when they are driven by the firing member,such as firing member 466, for example, yet prohibit, or at least limit,the gears from rotating in an opposite direction when the pawl of thefiring drive, such as pawl 170, for example, is retracted relative tothe firing member. In at least one embodiment, referring to FIG. 116,the ratchet mechanism can include leaf spring, or pawl, 1011 which canlimit the rotation of spur gear 416 as described in greater detailbelow.

Further to the above, when firing member 466, for example, is advancedby firing trigger 460, for example, firing member 466 can rotate spurgear 416 in a direction indicated by arrow D (FIG. 116) owing to theoperative engagement of pinion gear 401, intermediate gear 403, key gear406, and spur gear 416 as described above. When spur gear 416 is rotatedin direction D, in at least one embodiment, gear teeth 416 a of gear 416can be configured to contact and deflect pawl 1011 such that gear teeth416 a can pass thereby. However, in the event that firing member 466 isunintentionally retracted and/or spur gear 416 is rotated in a directionindicated by arrow H, pawl 1011 can be configured such that at least aportion thereof can be positioned intermediate two adjacent gear teeth416 a and prevent, or at least limit, spur gear 416 from rotating indirection H. In various embodiments, referring to FIG. 116, at least aportion of pawl 1011 can be wedged between gear teeth 416 a or ‘bite’into gear 416 such that gear 416 cannot substantially rotate indirection H, at least not until the reversing drive of the surgicalinstrument is operably engaged with the firing member as described ingreater detail below.

In various embodiments, the surgical instrument can include a returncarriage which can be moved between an unactuated position asillustrated in FIGS. 115 and 116 and an actuated position as illustratedin FIGS. 117 and 118 to place the surgical instrument in its reversingor retracting mode of operation. Similar to return carriage 494, in atleast one embodiment, return carriage 1094 can be rotated relative toframe 484 about pin 1094 a. In various embodiments, referring to FIG.118, pawl 1011 can be mounted to return carriage 1094 such that, whenreturn carriage 1094 is rotated downwardly into its actuated position,pawl 1011 can be moved out of operative engagement with spur gear 416.In such circumstances, spur gear 416 can be permitted to rotate in adirection indicated by arrow H when the surgical instrument is placed inits reversing mode. When spur gear 416 is permitted to rotate indirection H, the gear train can be permitted to rotate withoutinterference, or at least substantial interference, from the anti-backupmechanism such that the firing member can be retracted as outlinedabove. After the firing member has been sufficiently retracted, returncarriage 1094 can be rotated upwardly into its unactuated position andpawl 1011 can be operably re-engaged with spur gear 416.

In various circumstances, a reversing drive of a surgical instrument maybe prevented from being properly engaged with a firing member of thesurgical instrument. In at least one embodiment, the return carriage ofa reversing drive, such as return carriages 494 and 1094, for example,may not be able to properly contact and motivate firing pin 172 and/orreturn pin 498, for example. More particularly, the return carriage mayfail to properly displace firing pin 172 and/or return pin 498 such thatkey gear 406 is operably engaged with trigger 496 and, furthermore, suchthat pawl 170 is prevented from operably engaging firing member 466. Invarious embodiments, as outlined above, a return carriage can include abutton portion which can be configured to manually rotate the returncarriage downwardly when a force is applied thereto. In variouscircumstances, however, this force may have insufficient leverage tomove the return carriage, especially if the return carriage and/or oneof pins 172 and 498 is stuck in position, for example.

In various embodiments of the present invention, a surgical instrumentcan include a switch which can be better configured to manually engagethe reversing drive of the surgical instrument with the firing member.In at least one embodiment, referring to FIG. 119, the switch caninclude first and second portions, wherein first portion 1194 can bemovably connected relative to frame 1184, for example, and whereinsecond portion 1118 can also be movably connected relative to frame 1184as well. In various embodiments, first switch portion 1194 can bepivotably connected to frame 1184 such that, when first switch portion1194 is pivoted downwardly by a cam, similar to cam 402, for example,first portion 1194 can be configured to disengage return pin 498 andallow key portion 499 of return pin 498 to engage trigger gear 496 asdescribed above. In various embodiments, although not illustrated inFIG. 119, return carriage 1194 can include arm 1194d extending therefromwhich can be moved away from end 498 a of return pin 498 such that aspring, for example, can bias return pin 498 into operative engagementwith trigger gear 496.

In addition to the above, first switch portion 1194, when pivoteddownwardly, can be configured to contact return pin 172 and operablyengage key 222 of return pin 172 with pawl 170 such that pawl 170 cannotbe pivoted upwardly, as also described above. In effect, in at least onesuch embodiment, first switch portion 1194 can comprise a cam which canbe actuated to operably disengage the firing drive from, and operablyengage the reversing drive with, the firing member. In variouscircumstances, only the operation of first portion 1194 may be needed inorder to switch the surgical instrument between its advancing andreversing operating modes. In the event, however, that the cam of thereversing drive, such as cam 402, for example, cannot properly position,or actuate, first switch portion 1194, second portion 1118 of the switchmay be utilized to actuate first switch portion 1194 as described ingreater detail below.

Further to the above, second switch portion 1118 can be actuated inorder to actuate first switch portion 1194. In various embodiments,referring again to FIG. 119, second switch portion 1118 can includehandle 1118 b which can be configured to be grasped by a surgeon, forexample, such that the surgeon can apply a force thereto and rotateswitch portion 1118 about pivot 1118 a. In at least one embodiment,second switch portion 1118 can be configured to contact first switchportion 1184 and move first portion 1184 between its unactuated positionillustrated in FIG. 119 and its actuated position as described above. Invarious embodiments, in effect, second switch portion 1118 can comprisea cam which can contact first portion 1194 and drive first portion 1194downwardly such that first portion 1194 contacts firing pin 172 andreturn pin 498. In at least one such embodiment, referring to FIG. 119,second switch portion 1118 can include contact surface 1118 c which canbe configured to contact surface 1194 c of first switch portion 1194. Invarious embodiments, contact surface 1118 c can be positioned directlyabove contact surface 1194 c such that surfaces 1118 c and 1194 c can bealigned and the possibility of second switch portion 1118 not contactingfirst switch portion 1194 can be reduced.

In various embodiments, further to the above, contact surfaces 1118 cand 1194 c can be positioned and arranged such that a force, F₂, appliedto handle 1198 b has sufficient mechanical advantage to move firstswitch portion 1194 into its actuated position. In at least oneembodiment, handle force F₂ can be transmitted through the body ofsecond switch portion 1118 and to first switch portion 1194 via contactsurfaces 1118 c and 1194 c as transmission force F₃. Notably, in variousembodiments, transmission force F₃ can be different than handle force F₂Further to this point, referring to FIG. 119, the torques associatedwith handle force F₂ and transmission force F₃ in order to initiallymove first switch portion 1194 can be substantially the same, i.e., theproduct of distance Da and force F₂ can substantially equal the productof distance Db and force F₃, wherein distance Da can represent thedistance between pivot 1118 a and the application of force F₂, andwherein distance Db can represent the distance between pivot 1118 a andthe transmission of force F₃. Thus, when distance Da is smaller thandistance Db, as illustrated in FIG. 119, force F₂ can be larger thanforce F₃. Accordingly, in order for force F₃ to be substantially equalto force F₂, handle 1118 b would have to be positioned substantiallyabove surfaces 1118 c and 1194 c when force F₂ is applied to handle 1118b.

In various embodiments, further to the above, transmission force F₃ canbe transmitted through the body of first switch portion 1194 to firingpin 172 as displacement force F₁. Similar to the above, displacementforce F₁ can be different than transmission force F₃. Further to thispoint, referring again to FIG. 119, the torques associated withdisplacement force F₁ and transmission force F₃ in order to initiallydisplace firing pin 172 toward pawl 170, as outlined above, can besubstantially the same, i.e., the product of distance Dc and force F₁can substantially equal the product of distance Dd and force F₃, whereindistance Dc can represent the distance between pivot 1194 a and theapplication of force F₃, and wherein distance Dd can represent thedistance between pivot 1194 a and the transmission of force F₃. Thus,when distance Dc is smaller than distance Dd, as illustrated in FIG.119, force F₁ can be larger than force F₃. In effect, the smallertransmission force F₃ can be utilized to apply a larger displacementforce F₁ to firing pin 172, depending on the selection of distances Da,Db, Dc, and Dd. In various embodiments, as a result, the first andsecond portions of the switch can be configured such that force F₂supplied by the surgeon, for example, can be sufficient to manuallyposition the first portion of the switch in its actuated position viathe second portion of the switch and thereby manipulate the surgicalinstrument from an advancing operating mode to a reversing operatingmode, as outlined further above. In order to return the surgicalinstrument to its advancing operating mode, first switch portion 1194,for example can be rotated upwardly such that second switch portion 1118can also rotated upwardly, thereby resetting the switch assembly.

In a further exemplary embodiment, referring to FIGS. 120-122, asurgical instrument can include a switch assembly comprising firstportion 1294 which can be pivotably mounted to frame 1284 about pin 1294a and, in addition, a second portion 1218 which can be pivotably mountedto frame 1284 about pivot 1218 a. Although the first and second switchportions can be pivotably mounted to frame 1284, the switch portions canbe pivotably mounted to any other suitable portion of the surgicalinstrument. In various embodiments, similar to the above, first switchportion 1294 can be operated to switch the surgical instrument betweenadvancing and reversing operated modes. In at least one embodiment,first switch portion 1294 can be rotated between its unactuated positionillustrated in FIG. 120 and its actuated position illustrated in FIG.121. Similar to the above, second switch portion 1218 can be moveddownwardly by a force applied to handle 1218 b in order to move firstportion 1294 downwardly into its actuated position.

In various embodiments, second switch portion 1218, for example, and thefiring trigger of the surgical instrument, such as firing trigger 460,for example, can be configured such that second portion 1218 can beprevented, or at least substantially prevented, from being rotateddownwardly unless the firing trigger is in its unactuated position. Byrequiring that the firing trigger be in its unactuated position beforeallowing the switch to be operated, first switch portion 1294 of thereversing mechanism may be properly aligned with the firing pin of thefiring drive, such as firing pin 172, for example, when first portion1294 is rotated downwardly. In various embodiments, the surgicalinstrument can be configured such that the firing pin is positionedwithin a predetermined range such that the firing pin can be contactedby first switch portion 1294 and slid into engagement with the pawl ofthe firing drive, such as pawl 170, for example.

In various embodiments, referring to FIG. 50, surgical instrument 100can include end effector 106 and elongate shaft assembly 104, where endeffector 106 and shaft assembly 104 can be pivotably connected byarticulation joint 114. As outlined above, articulation joint 114 canallow end effector 106 to be moved, or articulated, relative to shaftassembly 106 about axis 116. In various circumstances, a surgeon canarticulate end effector 106 to more easily access a surgical site withina patient's body. More particularly, a surgeon may insert end effector106 and shaft assembly 104 through a cannula at least partially insertedinto the patient's body and, once end effector 106 has passed throughthe cannula, end effector 106 can be pivoted, or articulated, in orderto position end effector 106 relative to soft tissue, for example, inthe surgical site that is to be stapled and/or incised. Once endeffector 106 has been positioned, the relative relationship between endeffector 106 and shaft assembly 104 can be fixed, or locked, by alocking mechanism as described in greater detail further below.

In at least one embodiment, referring to FIGS. 51 and 52, articulationjoint 114 can include end effector lock member 300 and pivot 302. Invarious embodiments, referring to FIGS. 53-56, end effector lock member300 can include connector portion 320 which can secure lock member 300to end effector 106 and, referring to FIG. 52, shaft assembly 104 caninclude pivot connector 342, where pivot connector 342 can include pivot302 extending therefrom. In various embodiments, lock member 300 caninclude aperture 301 which can be sized and configured to receive atleast a portion of pivot 302 therein. In at least one embodiment, pivot302 and aperture 301 can be configured such that end effector 106 canrotate freely about axis 116. In other various embodiments, pivot 302and aperture 301 can be configured such that friction between pivot 302and aperture 301 can resist, although permit, relative movement betweenend effector 106 and shaft assembly 104. Although not illustrated,articulation joint 114 can include more than one axis, or pivot, aboutwhich end effector 106 can be rotated.

In various embodiments, a surgeon can articulate end effector 106relative to shaft assembly 104 by pushing end effector 106 against acavity side wall surrounding a surgical site, for example, and applyinga force to shaft assembly 104 such that end effector 106 pivots aboutaxis 116. Thereafter, if the surgeon desires to re-center end effector106, i.e., orient end effector 106 and shaft assembly 104 along a line,the surgeon can place end effector 106 against a cavity side wall onceagain, for example, and a apply a force to shaft assembly 104 asdescribed above. In various embodiments, referring to FIGS. 51 and 52,surgical instrument 100 can include a re-centering mechanism which canautomatically re-center, or at least substantially re-center, endeffector 106 relative to shaft assembly 104. In various embodiments, endeffector lock member 300 can include centering surfaces 316 and elongateshaft assembly 104 can include centering shafts 328 and biasing members330, where biasing members 330 can be configured to bias centeringshafts 328 against centering surfaces 316. In at least one suchembodiment, centering surfaces 316 can be disposed on substantiallyopposite sides of axis 116 such that centering shafts 328 can apply asubstantially equal torque, or moment, to lock member 300 and, absent anadditional motivating force, hold end effector 106 in a substantiallycentered position. When end effector 106 is articulated by such amotivating force, as described above, lock member 300 can be configuredto displace one of centering shafts 328 proximally and compress thebiasing member 330 operably engaged therewith. More particularly, thebiasing member 330 can be positioned between a guide 331 and at leastone projection 329 extending from centering shaft 328 such that, whenprojection 329 is moved proximally by shaft 328, biasing member 330 iscompressed therebetween. After the motivating force is removed, thecompressed biasing member 330 can expand and rotate lock member 300 toits center position via centering shaft 328, or to a position where thetorque applied by biasing members 330 is substantially balanced.Although biasing member 330 is illustrated as a coil spring, biasingmember 330 can include any suitable elastic member.

In various embodiments, a locking mechanism can be used to hold endeffector 106 in its articulated position even after the motivating forcehas been removed. In at least one embodiment, referring to FIGS. 53-56,end effector lock member 300 can include a first portion having firstsurface 308, a second portion having second surface 304, teeth 312, andrecesses 314 defined between teeth 312 where, as described in greaterdetail further below, teeth 312 and recesses 314 can be configured to beoperably engaged with a shaft assembly locking member in order to fix,or lock, the relative relationship between end effector 106 and shaftassembly 104. In various embodiments, teeth 312 and recesses 314 can bepositioned intermediate first surface 308 and second surface 304. In atleast one embodiment, first surface 308 can extend from aperture 301 tofirst perimeter 310, and second surface 304 can extend from aperture 301to second perimeter 306. In various embodiments, first perimeter 310 candefine a first plane and second perimeter 306 can define a second planewhere teeth 312 and recesses 314 can be positioned intermediate thefirst and second planes. In embodiments where first perimeter 310 isdifferent than second perimeter 306, teeth 312 can extend at an angle,or bevel, therebetween. In various embodiments, a tooth 312 canintersect first perimeter 310 at a point further away from axis 116 thana point at which the tooth 312 intersects second perimeter 306. In atleast one embodiment, at least one of the teeth 312 can define a firstaxis 313 which can extend between first surface 308 and second surface304 in a direction which is not perpendicular to first surface 308and/or axis of rotation 116. In such embodiments, teeth 312 can slideover soft tissue, for example, which is positioned adjacent toarticulation joint 114. Stated another way, owing to the angled, orbeveled, surfaces of teeth 112, the probability of teeth 112 catchingon, or impinging upon, the soft tissue surrounding articulation joint114 when end effector 106 is articulated can be reduced. In at least oneembodiment, teeth 312 may not extend beyond first perimeter 310 suchthat, in the event that at least a portion of first perimeter 310 is incontact with soft tissue, for example, first perimeter 310 and teeth 312can, as above, easily slide relative to the soft tissue.

Further to the above, embodiments of the present invention can providesignificant advantages over previous surgical instruments. Moreparticularly, referring to FIG. 57, the articulation joints of previousend effectors have included lock members, such as lock member 299, forexample, which include teeth 298 that extend outwardly from theperimeter of the lock member. As a result, when the end effector isarticulated relative to the shaft assembly of the surgical instrument,teeth 298 can catch on, or impinge upon, the surrounding soft tissue andpotentially cause trauma thereto. In various circumstances, tissue canbe caught between adjacent teeth 298 such that, when the end effector isarticulated, the soft tissue can be pulled into the articulation jointand can be pinched by the relatively moving components of the joint. Inembodiments of the present invention in which the teeth of the lockmember are angled, or beveled, as outlined above and illustrated in FIG.58, the soft tissue can more easily flow over the teeth and reduce thepossibility that the soft tissue can be pulled into the articulationjoint.

As outlined above, referring to FIGS. 59-62, surgical instrument 100 canfurther include locking member 120 which can be slid relative to endeffector 106 and can be operably engaged with end effector 106 toprevent, or at least limit, relative movement between shaft assembly 104and end effector 106. In at least one embodiment, lock member 120 can beconfigured to engage at least one of teeth 312 such that end effector106 is prevented from moving relative to lock member 120. Moreparticularly, lock member 120 can include end portion 338 and shaftportion 340, where end portion 338 can include recess 336 which can beconfigured to receive a tooth 312 of lock member 300 in a close-fit, oreven interference-fit, relationship. In various alternative embodiments,locking portion 338 can be received within at least one of recesses 314in a close-fit, or interference-fit, relationship similar to the above.In either event, surgical instrument 100 can further include spring 126which can be configured to bias lock member 120 into engagement with endeffector lock member 300. In the event that recess 336 is not alignedwith a tooth 312, in at least one embodiment, the biasing force appliedto lock member 120 by spring 126 can cause lock member 120 to contactand rotate end effector lock member 300 about axis 116 until one ofteeth 312 is aligned with recess 336. In various embodiments, spring 126can comprise any suitable biasing member including a helical spring,leaf spring, or other biasing material.

In various alternative embodiments, referring to FIGS. 63-67, a surgicalinstrument can include end effector lock member 350 comprising aperture301, a first portion including first surface 358, a second portionincluding second surface 354 (FIG. 67), and connector portion 320. Endeffector lock member 350 can also comprise teeth 362 and recesses 364defined between teeth 362 where, in at least one embodiment, teeth 362and recesses 364 can be positioned intermediate first surface 358 andsecond surface 354. In various embodiments, referring to FIGS. 65-67,teeth 362 may not extend beyond first perimeter 357 of first surface 358and/or second perimeter 353 of second surface 354. In at least one suchembodiment, teeth 362 may be completely positioned, or contained,between first surface 358 and second surface 354. In at least onealternative embodiment, teeth 362 may partially extend from firstperimeter 357 and/or second perimeter 353. In various embodiments, firstperimeter 357 and second perimeter 353 can define an outer surfacetherebetween where recesses 364 can be defined in the outer surface. Asa result of the above-described features, end effector lock member 350can slide relative to soft tissue positioned adjacent to thearticulation joint without impinging on the soft tissue. In variousembodiments, teeth 362 may be blunted or rounded to further facilitatethe relative sliding described above. In at least one embodiment,referring to FIGS. 63-65, a locking mechanism can be configured toengage at least one of teeth 362 and recesses 364 and can include lockmember 382 comprising end portion 388 and shaft portion 390. In at leastone embodiment, similar to the above, end portion 388 can include recess394 which can be configured to engage at least one of teeth 362, forexample.

In various embodiments, referring now to FIG. 123, surgical instrument1300 can comprise, similar to the above, an end effector 1306 rotatablycoupled to a shaft 1304 about an articulation joint 1315. Also similarto the above, the surgical instrument 1300 can comprise means foropening and closing anvil 1312 relative to staple cartridge channel 1308and, in addition, means for permitting end effector 1306 to bearticulated about axis 1316 of articulation joint 1315. With regard tothe means for opening and closing anvil 1312, the surgical instrument1300 can comprise a closure tube comprising a distal tube component 1334a and a proximal tube component 1334 b which, when advanced distally,i.e., in a direction indicated by arrow Z, can engage anvil 1312 andcam, or rotate, anvil 1312 downwardly toward staple cartridge channel1308. Correspondingly, when the closure tube is retracted in a directionopposite of arrow Z, the distal tube component 1334 a can cam anvil 1312upwardly away from staple cartridge channel 1308 and/or permit a springto bias anvil 1312 into an open position.

In various embodiments, referring now to FIGS. 124 and 125, distal tubecomponent 1334 a can be advanced distally such that it at leastpartially encompasses anvil 1312 and staple cartridge channel 1308. Inat least one embodiment, the distal tube portion 1334 a can comprise acam portion 1335 which can be configured to contact the anvil 1312 andslide over the outside surface 1337 of anvil 1312. In addition, the camportion 1335 can be configured to slide over the outside surface 1319 ofstaple cartridge channel 1318 such that the distal tube portion 1334 acan encompass the entire perimeter, or an least substantial portion ofthe perimeter, of anvil 1312. In at least one embodiment, the camportion 1335 can comprise a continuous circular, or at leastsubstantially circular, ring of material defining an aperture configuredto control the position of anvil 1312 relative to staple cartridgechannel 1318 and gap, if any, between the anvil 1312 and a staplecartridge positioned within the staple cartridge channel 1318. Incertain embodiments, at least one spring, or biasing member, can bepositioned intermediate the anvil 1312 and the staple cartridge channel1318, wherein the spring can be configured to bias the anvil 1312 and/orstaple cartridge channel 1318 against an inner perimeter of the distaltube portion 1334 a aperture.

In various embodiments, referring again to FIG. 125, the distal tubeportion 1334 a can comprise a distal edge 1333 which can define thedistal-most portion of cam portion 1335 in contact with anvil 1312 andstaple cartridge channel 1318. In certain embodiments, the staplecartridge channel 1318, for example, can comprise a forward stop, suchas stop 1331, for example, configured to limit the distal movement ofdistal tube portion 1334 a. In at least one such embodiment, the distaledge 1333 can contact stop 1331 and, as a result, limit the distance inwhich cam portion 1335 can slide over anvil 1312. In certaincircumstances, however, the limitation of the distance in which camportion 1335 can slide over anvil 1312 can limit the amount of clampingforce, or leverage, that the anvil 1312 can apply to tissue positionedintermediate the anvil 1312 and a staple cartridge positioned withinstaple cartridge channel 1318.

In various alternative embodiments, referring now to FIGS. 126-128, adistal tube portion 1334 a′ can comprise a first cam portion 1335 a′configured to engage the anvil 1312 and, in addition, a second camportion 1335 b′ configured to engage the staple cartridge channel 1318.Much like distal tube portion 1334 a, distal tube portion 1334 a′ canencompass, or at least substantially encompass, a portion, or perimeter,of end effector 1306 defined by anvil 1312 and staple cartridge channel1318. In various embodiments, however, the cam portion 1335 a′ canextend distally a greater distance than cam portion 1335 b′. In at leastone such embodiment, as a result, the cam portion 1335 a′ can extend agreater distance over, or around, anvil 1312 than cam portion 1335 b′can extend under, or around, staple cartridge channel 1308. Asillustrated in FIG. 127, the distal tube portion 1334 a′ can comprise adistal edge 1333 a′ which is positioned distally with respect a distaledge 1333 b′ such that, referring to FIG. 128, the cam portion 1335 a′can extend over a longer distance of anvil 1312 and provide a largerclamping force, or leverage, as compared to the cam portion 1335 ofdistal tube portion 1334 a. In various circumstances, as a result, thecam portion 1335 a′ can extend a greater distance over anvil 1312 beforethe cam portion 1335 b′ comes into contact with stop 1331.

In various embodiments, referring again to FIG. 126, the inner perimeterof cam portion 1335 a′ can comprise an arcuate or an least partiallycircular inner profile which matches, or at least substantially matches,an arcuate or an least partially circular outer profile of anvil 1312.In at least one such embodiment, the inner profile of cam portion 1335a′ can be configured to provide a close fit with the outer profile ofanvil 1312 such that there is little, if any, relative transverse, orradial, movement therebetween yet configured to permit the cam portion1335 a′ to slide relative to anvil 1312 as distal tube portion 1334 a′is moved distally in the direction of arrow Z. Similar to the above, theinner perimeter of cam portion 1335 b′ can comprise an arcuate or anleast partially circular inner profile which matches, or at leastsubstantially matches, an arcuate or an least partially circular outerprofile of staple cartridge channel 1308. In at least one suchembodiment, the inner profile of cam portion 1335 b′ can be configuredto provide a close fit with the outer profile of staple cartridgechannel 1308 such that there is little, if any, relative transverse, orradial, movement therebetween yet configured to permit the cam portion1335 b′ to slide relative to anvil 1312 as distal tube portion 1334 a′is moved distally in the direction of arrow Z.

As outlined above, referring again to FIG. 123, the end effector 1306can be rotated relative to the shaft 1304 about articulation joint 1315.In various embodiments, the closure tube comprising distal tube portion1334 a and proximal tube portion 1334 b can comprise one or morearticulation links, such as links 1301 a and 1301 b, for example, whichcan permit distal tube portion 1334 a to rotate relative to proximaltube portion 1334 b when end effector 1306 is rotated relative to shaft1304. In at least one embodiment, link 1301 a and/or link 1301 b cancomprise projections 1303, for example, which can be positioned withinapertures in tube portions 1334 a and 1334 b, for example, such thatlinks 1301 a and 1301 b can pivot relative to proximal tube portion 1334b and such that distal tube portion 1334 a can rotate relative to links1301 a and 1301 b. In various other embodiments, the links 1301 a, 1301b and closure tube portions 1334 a, 1334 b can comprise any suitablecombination of projections and apertures to permit articulationtherebetween. In any event, the links 1301 a and 1301 b can provide morethan degree of freedom between distal tube portion 1334 a and proximaltube portion 1334 b. More particularly, the links 1301 a and 1301 b canprovide at least two degrees of freedom, i.e., a first degree of freedombetween proximal tube portion 1334 b and links 1301 a, 1301 b and asecond degree of freedom between links 1301 a, 1301 b and distal tubeportion 1334 a.

In use, as outlined above, the end effector 1306 can be articulatedrelative to shaft 1304 about axis 1316 and then locked into position bya lock. Referring now to FIG. 129, the pivot axis 1316 of articulationjoint 1315 can be defined by a pivot 1302 extending from shaft channelportion 1342 wherein the pivot 1302 can be positioned within an aperturein lock portion 1305 of staple cartridge channel 1308. When the lock isdisengaged from lock portion 1305, the end effector 1306 can be rotatedor pivoted about axis 1316 into a desired position and then locked intoplace by re-engaging the lock with lock portion 1305. In variousembodiments, the end effector 1306 in first and second, or left andright, directions about pivot 1302. Similar to the embodiments describedabove, the lock can engage at least one of lock teeth 1312 and/or atleast one of recesses 1314 positioned intermediate lock teeth 1312.Regardless of whether the end effector 1306 is in a centered position oran articulated position, the closure tube 1334 of shaft 1304 can beadvanced distally in order to close anvil 1312, as described above. Whenclosure tube 1334 is advanced distally, the links 1301 a and 1301 b canslide relative to axis 1316 and articulation joint 1315 owing, invarious circumstances, to the multiple degrees of freedom afforded bylinks 1301 a and 1301 b as described above eventhough the end effector1306 may be articulated relative to shaft 1304, for example.

Once the closure tube 1334 has been advanced and the anvil 1312 has beenclosed, a drive bar, such as drive bar 1390 (FIG. 136), for example, canbe advanced within the shaft 1304 and the end effector 1306. In variousembodiments, referring to FIGS. 136 and 137, drive bar 1390 can comprisea bar portion 1391 configured to transmit a force from a trigger of thesurgical instrument handle (FIG. 1), for example, to a cutting member1392 and/or a staple driver 1393 such that the cutting member 1392 canincise tissue positioned within end effector 1306 and/or such thatstaple driver 1393 can eject staples, such as staple 1381 (illustratedin phantom in FIG. 136), for example, from a staple cartridge, such asstaple cartridge 1380 (FIG. 138), for example, positioned in staplecartridge channel 1308. Turning now to FIGS. 129, the lock portion 1305of end effector 1306 can comprise a guide slot 1321 configured toreceive and guide bar portion 1391 of drive bar 1390. In addition, theshaft 1304 can further comprise a frame, or spine 1345 (FIGS. 131 and132) including a guide slot 1341 also configured to receive guide barportion 1391 of drive bar 1390, wherein the drive bar 1390 can slidewithin guide slots 1321 and 1341 when the drive 1390 is advanceddistally and/or retracted proximally.

In various embodiments, referring now to FIGS. 129 and 130, the surgicalinstrument 1300 can further comprise a guide member 1370 which cancomprise a guide slot configured to receive at least a portion of drivebar 1390. In at least one embodiment, the guide slot within guide member1370 can comprise a first sidewall 1371 and a second sidewall 1372 whichcan be configured to support the bar portion 1391 (illustrated withphantom lines in FIG. 129) when the drive bar 1390 is moved relative toarticulation joint 1315. More particularly, when end effector 1306 isarticulated in a first, or left, direction, as illustrated in FIG. 129,the first sidewall 1371 can be configured to support the bar portion1391 of drive bar 1390 as bar portion 1391 is slid relative thereto. Invarious embodiments, the bar portion 1391 may be sufficiently flexiblein order to adopt a change in geometry so as to fit and move withinguide slot 1341 and guide slot 1321. In certain circumstances, the guidemember 1970 can be configured to assist in preventing the bar 1391 frombuckling under the load applied thereto. Similar to the above, thesecond sidewall 1372 can be configured to support the bar portion 1391when the end effector 1306 is articulated in a second, or right,direction.

In various embodiments, referring again to FIGS. 129-130, the guidemember 1370 can move independently of shaft 1304 and/or end effector1306. More particularly, in at least one embodiment, the guide member1370 can be configured to float, or adopt its own position, relative tolock portion 1305 of end effector 1306 and frame 1341 (FIGS. 131 and132) of shaft 1304, including when end effector 1306 is articulatedrelative to shaft 1304. In certain embodiments, the guide member 1370can comprise means for permitting, although limiting, the relativemovement between guide member 1370. In at least one such embodiment, theguide member 1370 can comprise a first projection, or boss, 1376extending therefrom which can be positioned within a first boss slot1343 in shaft channel portion 1342, wherein the sidewalls of boss slot1343 are sufficiently spaced from one another to permit end 1378 ofguide member 1370 to move relative to shaft 1304 yet limit the range ofmovement therebetween. Similarly, the guide member 1370 can furthercomprise a second projection, or boss, 1377 extending therefrom whichcan be positioned within a second boss slot 1322 of lock portion 1305,wherein the sidewalls of boss slot 1345 are sufficiently spaced from oneanother to permit end 1379 of guide member 1370 to move relative toshaft 1304 yet limit the range of movement therebetween. In variousalternative embodiments, the guide member 1370 could comprise first andsecond boss slots and the shaft channel portion 1342 and lock portion1305 could comprise bosses extending therefrom.

In various embodiments, further to the above, the first boss slot 1343of shaft channel portion 1342 and the first boss 1376 of guide member1370 can be configured to keep the proximal end 1378 of the slot ofguide member 1370 aligned, or at least substantially aligned, with theguide slot 1341 in shaft 1304. Similarly, the second boss 1377 of guidemember 1370 and the second boss slot 1322 of lock portion 1305 can beconfigured to keep the distal end 1379 of the guide slot in guide member1370 aligned, or at least substantially aligned, with the guide slot1321 in end effector 1306. In various embodiments, further to the above,the lock portion 1305, for example, can comprise recesses 1323 a and1323 b configured to receive and accommodate the distal corners, or end,of guide member 1370 when end effector 1306 and lock portion 1305 arearticulated with respect to shaft 1304, for example. In at least oneembodiment, referring primarily to FIG. 130, the recesses 1323 a and1323 b can be configured to provide clearance between the sidewalls ofrecesses 1323 a and 1323 b and the end of guide member 1370.

In various alternative embodiments, referring now to FIGS. 133 and 134,the end effector 1306 can comprise an alternative embodiment of the lockportion 1305, i.e., lock portion 1305′. The lock portion 1305′ cancomprise recesses 1323 a′ and 1323 b′ which can be configured to receiveand support the distal end of guide member 1370, as described in greaterdetail below. Referring to FIG. 133, the end effector 1306 isillustrated in a straight, or at least substantially straight, alignmentwith shaft 1304, wherein a gap 1329 is present intermediate guide member1370 and lock portion 1305 and, in addition, a gap 1349 is presentintermediate guide member 1370 and frame, or spine, 1345. In such aposition, the guide slot 1341, the guide slot in guide member 1370, andthe guide slot 1321 in lock portion 1305 can be aligned, or at leastsubstantially aligned, with one another along a common axis. In suchcircumstances, the knife bar 1390 may be subjected to an axial loadalong the axis 1394 during use, although it may be subjected to little,if any, transverse loads which are transverse to axis 1394 and, as aresult, the sidewalls of the guide slots may be required to providelittle, if any, transverse support to the sides of driver bar 191.

Referring now to FIG. 134, the end effector 1306 is illustrated in anarticulated alignment with shaft 1304, as illustrated by the rotation oflock portion 1305′. As also illustrated in FIG. 134, the guide member1370 has also moved in response to the articulation of end effector1306. In various embodiments, the movement of end effector 1306 and lockportion 1305′ can cause lock portion 1305′ to contact guide member 1370and at least one of, one, rotate guide member 1370 in the same directionas end effector 1306 is being rotated and, two, push guide member 1370proximally toward frame 1345 of shaft 1304. As illustrated in FIG. 134,the gap 1329 between the distal end of guide member 1370 and lockportion 1305 has been one of eliminated or substantially reduced. Asalso illustrated in FIG. 134, at least a portion of guide member 1370can be positioned within first recess 1323 a′ such that relativemovement between the distal end of guide member 1370 and lock portion1305 can be prevented, or at least substantially inhibited. Moreparticularly, in at least one embodiment, a catch 1373 a extending fromguide member 1370 can be positioned within first recess 1323 such thatrelative movement between catch 1373 a and lock portion 1305 isprevented, or at least limited, and such that a desired alignmentbetween first sidewall 1371 and a first sidewall 1321 a of guide slot1321 can be substantially maintained. Owing to the elimination, orreduction, of gap 1329 and the alignment, or at least substantialalignment, of first sidewall 1371 and first sidewall 1321 a, the drivebar 1391 can be supported so as to eliminate, or at least reduce, thepossibility of drive bar 1391 buckling in a transverse direction, forexample.

In various circumstances, further to the above, the end effector 1306can be rotated in a second direction, or direction opposite the firstdirection, for example. In such circumstances, similar to the above, theguide member 1370 can move in response to the articulation of endeffector 1306. In various embodiments, the movement of end effector 1306and lock portion 1305′ can cause lock portion 1305′ to contact guidemember 1370 and at least one of, one, rotate guide member 1370 in thesame direction as end effector 1306 is being rotated and, two, pushguide member 1370 proximally toward frame 1345 of shaft 1304. In suchcircumstances, also similar to the above, the gap 1329 between thedistal end of guide member 1370 and lock portion 1305 can be one ofeliminated or substantially reduced and at least a portion of guidemember 1370 can be positioned within second recess 1323 b′ such thatrelative movement between the distal end of guide member 1370 and lockportion 1305 can be prevented, or at least substantially inhibited. Moreparticularly, in at least one embodiment, a catch 1373 b extending fromguide member 1370 can be positioned within second recess 1323 b′ suchthat relative movement between catch 1373 a and lock portion 1305 isprevented, or at least limited, and such that a desired alignmentbetween second sidewall 1372 and a second sidewall 1321 a of guide slot1321 can be substantially maintained. Owing to the elimination, orreduction, of gap 1329 and the alignment, or at least substantialalignment, of second sidewall 1372 and second sidewall 1321 b, the drivebar 1391 can be supported so as to eliminate, or at least reduce, thepossibility of drive bar 1391 buckling in a transverse direction, forexample.

In various embodiments, further to the above, the second boss 1377extending from guide member 1370 can be configured to work in concertwith catches 1373 a or 1373 b to prevent, or at least substantiallyinhibit, relative movement between the distal end of guide member 1370and lock portion 1305′. More particularly, in at least one embodiment,the second boss 1377 and the second boss slot 1322 can be configuredsuch that second boss 1377 is in contact with a sidewall of the secondboss slot 1322 when first catch 1373 a is positioned within first recess1323 a′. Owing to the above, the distal end of guide member 1370 can beprevented, or at least inhibited, from translating and/or rotatingrelative to lock portion 1305′. In various circumstances, the firstcatch 1373 a can be positioned within the first recess 1323 a′ withoutthe second boss 1377 being in contact with a sidewall of second bossslot 1322. In at least one such circumstance, the displacement of drivebar 1390 can cause guide member 1370 to rotate relative to lock portion1305′ and cause second boss 1377 to be positioned against a sidewall ofsecond boss slot 1322.

When the end effector 1306 is rotated in its second direction, similarto the above, the second boss 1377 and the second boss slot 1322 can beconfigured such that the second boss 1377 is in contact with a sidewallof second boss slot 1322 when second catch 1373 b is positioned withinsecond recess 1323 b′. Owing to the above, the distal end of guidemember 1370 can be prevented, or at least inhibited, from translatingand/or rotating relative to lock portion 1305′. In variouscircumstances, the second catch 1373 b can be positioned within thesecond recess 1323 b′ without the second boss 1377 being in contact witha sidewall of second boss slot 1322. In at least one such circumstance,the displacement of drive bar 1390 can cause guide member 1370 to rotaterelative to lock portion 1305′ and cause second boss 1377 to bepositioned against a sidewall of second boss slot 1322.

As discussed above, the end effector 1306 can be rotated through a rangeof articulation angles relative to shaft 1304. For example, the endeffector 1306 can be rotated between a straight, or center, alignment,as illustrated in FIG. 133, and an articulated alignment, as illustratedin FIG. 134. In the articulated alignment of FIG. 134, the end effector1306 can be rotated approximately 45 degrees, for example, from thestraight, or center, alignment. In other circumstances, referring now toFIGS. 131 and 132, the end effector 1306 can be rotated approximately 75degrees, for example, from the straight, or center, alignment. When endeffector 1306 is rotated, as outlined above, the lock portion 1305′ can,in various embodiments, rotate guide member 1370 owing to the operativeengagement between first catch 1373 a of guide member 1370 and firstrecess 1323 a′ of lock portion 1305′, for example. Furthermore, as alsooutlined above, the rotation of lock portion 1305′ can push guide member1370 proximally toward frame 1345. In various embodiments, the guidemember 1370 can comprise a proximal projection, or catch, 1375 which canbe configured to slide within a recess in shaft 1304 when the guidemember 1370 is pushed proximally. In at least one such embodiment, theproximal catch 1375 can be slid into a recess 1349 defined intermediatethe frame 1345 and the proximal shaft portion 1341. In suchcircumstances, the proximal end 1375 of the guide member 1370 can beprevented, or at least inhibited, from lifting upwardly relative toframe 1345. In addition, in at least one embodiment, the first boss 1376and the first boss slot 1343 can work in concert with proximal catch1375 and the catch recess 1349 in shaft 1304 in order to prevent, or atleast limit, relative translation and/or rotation between the proximalend of guide member 1370 relative to shaft 1304.

As discussed above, the end effector 1306 can be articulated relative toshaft 1304 about axis 1316 through a range of positions, ororientations. When end effector 1306 is in a straight, or centered,orientation as illustrated in FIG. 133, the distance between the distalend of guide slot 1341, i.e., datum 1330, and the proximal end of guideslot 1321, i.e., datum 1331, can be defined by a first distance 1332 a.When end effector 1306 is in an articulated orientation as illustratedin FIG. 134, the distance between datum 1330 and datum 1331 can bedefined by a second distance 1332 b. Owing to the articulation of endeffector 1306 and the movement of datum 1331 toward datum 1330, thesecond distance 1332 b is shorter than the first distance 1332 a.Similarly, when end effector 1306 is further articulated into theorientation illustrated in FIG. 131, the distance between datum 1330 anddatum 1331 can be defined by a third distance 1332 c which is shorterthan the first distance 1332 a and the second distance 1332 b. In anyevent, the reader will understand that the particular degrees ofarticulation of the end effector 1306 depicted in FIGS. 131, 133, and134 are exemplary and that the end effector 1306 can be articulated intoany other suitable orientation wherein, in such other orientations, thedistance between datums 1330 and 1331 may be different.

In various circumstances, the cutting member 1392 can be positionedwithin the staple cartridge 1380 (FIG. 138) when the end effector 1306is in its straight and/or articulated orientations. When the endeffector 1306 is in its straight orientation, the cutting member 1392can be positioned in a first position relative to the distal end 1382 ofthe staple cartridge 1380 and/or the distal end 1384 of cutting knifeslot 1383. When the end effector 1306 is articulated relative to shaft1304, as discussed above, one of the cutting member 1392 and the staplecartridge 1380 may move relative to the other leaving the cutting member1392 in a second position relative to the distal end 1382 of staplecartridge 1380 and the distal end 1384 of cutting knife slot 1383. Invarious circumstances, this second position can be closer to the distalend 1382 and distal end 1384 than the first position. In suchcircumstances, depending on the degree of the articulation, the cuttingmember 1392 may have a starting position which is closer to the distalend 1382 and the distal end 1384 when the cutting member 1392 isadvanced distally by the drive bar 1390. Such different startingpositions can result from, one, the cutting member 1392 being held inposition, or at least partially held in position, by the stiffness ofthe drive bar 1390 such that the cutting member 1392 slides within thestaple cartridge 1380 when the end effector 1306 is articulated and,two, the distance (1332 a, 1332 b, and 1332 c) between datums 1330 and1331 changing as the end effector 1306 is articulated, as discussedabove.

In some circumstances, further to the above, the distance between theinitial position of the cutting member 1392 and the distal ends 1382,1384 may be the same, or at least the substantially the same, in theminor-image orientations of the end effector 1306. More particularly,the distance between the initial position of the cutting member 1392 andthe distal ends 1382, 1384 may be the same when the end effector isarticulated in a 45 degree angle to the left of the center orientationas compared to a 45 degree angle to the right of the center orientation,for example. In various embodiments, the initial position of cuttingmember 1392 may be closest to the distal ends 1382, 1384 when the endeffector is at its maximum articulation angle in either direction, leftor right. In certain embodiments, the initial position of cutting member1392 may be furthest away from the ends 1382, 1384 when the end effector1306 is in its straight, or center, orientation.

In use, as described above, the drive bar 1390 can be advanced distallyin order to incise tissue positioned within the end effector 1306 and/oreject staples positioned within the staple cartridge 1380 (FIG. 138). Insome embodiments, a surgical stapling instrument can be configured suchthat the drive bar 1390 is advanced a predetermined, or set, distance bya trigger mechanism, or firing mechanism, of the surgical instrumentduring use. Stated another way, in various embodiments, such a surgicalinstrument can be configured to advance the cutting member 1392 apredetermined, or set, distance without regard to whether end effector1306 is articulated and/or without regard to the degree of articulationof end effector 1306. In various circumstances, however, the cuttingmember 1392 may stop at different distal positions within the staplecartridge 1380 owing to the different starting positions of the cuttingmember 1392. More particularly, referring to FIGS. 137 and 138, thecutting edge 1396 of cutting member 1392 can be advanced to a position1389 a when the end effector 1306 is in its straight orientation (FIG.133) and to a different, more distal, position 1389 c when the endeffector is in a fully articulated, or nearly fully articulated,orientation (FIG. 131) eventhough the cutting member 1392 has beenadvanced the same predetermined, or set, distance.

In various circumstances, the different final positions of cuttingmember 1392 and cutting edge 1396 can result from the different startingpositions of cutting member 1392 within the staple cartridge 1380. Asdescribed above, the different starting positions of cutting member 1392can result from the articulation of end effector 1306, the stiffness ofdrive bar 1391, and the different distances, such as distances 1332 aand 1332 c, for example, between the datums 1330 and 1331 that existwhen the end effector 1306 is in its straight orientation (FIG. 133) andarticulated orientations (FIG. 131). In various circumstances, asdistance 1323 c is shorter than distance 1323 a, the cutting member 1392can be positioned in a more distal initial position in staple cartridge1380 (as compared to its position when the end effector 1306 is in itsstraight orientation) before the predetermined or set displacement ofthe cutting member 1392 is applied thereto and, in variouscircumstances, the cutting edge 1396 can be advanced to a more distalposition within the staple cartridge 1380 to position 1389 c.Correspondingly, as distance 1323 a is longer than distance 1323 c, thecutting member 1392 can be positioned more proximally in the staplecartridge 1380 (as compared to its position when the end effector 1306is in a fully articulated orientation) before the predetermined, or set,displacement of the cutting member 1392 is applied thereto and, invarious circumstances, the cutting edge 1396 may only be advanced toposition 1389 a. Similar to the above, the cutting edge 1396 could beadvanced to a position intermediate position 1323 a and position 1323 cwhen the end effector 1306 is only in a partially articulatedorientation (FIG. 134).

Referring again to FIG. 138, staple cartridge 1380 can comprise aplurality of staple cavities, such as staple cavities 1385, for example,and staples, such as staples 1381 (FIG. 137), for example, positioned inthe staple cavities 1385. In various embodiments, each staple 1381 cancomprise one or more staple legs, such as staple legs 1381 p and 1381 d,for example, wherein, in at least one embodiment, each staple cavity1385 can be configured to receive a staple 1381 such that its staple leg1381 d is positioned in a distal end 1385 d of the staple cavity 1385and such that its staple leg 1381 p is positioned in the proximal end1385 p, of the staple cavity 1385. In various embodiments, it may bedesirable for the cutting edge 1396 of cutting member 1392 to be stoppedbefore it crosses an end datum 1386 wherein, in certain embodiments, theend datum 1386 can be defined by and extend through the distal-moststaple leg, or legs, 1381 d, of the distal most staple, or staples,1381, for example. In other various embodiments, the end datum 1386could be defined by and extend through any portion of the distal-moststaple cavities 1385, for example. In certain embodiments, the end datum1386 could be defined by and extend through the proximal-most staplelegs 1381 p positioned within the distal-most staple cavities 1385. Inany event, when cutting edge 1396 is stopped before the end datum 1386,the cutting edge 1396 may not transect beyond the tissue that has beenstapled by staples 1381. In various embodiments, it may be desirable forthe cutting edge 1396 to be stopped at least 3 mm short of end datum1386. In certain embodiments, it may be desirable for the cutting edge1396 to be stopped in a range between approximately 3 mm andapproximately 7 mm short of end datum 1386. In certain otherembodiments, a narrower range may be desired. Described herein are meansand embodiments for controlling or limiting the advancement of thecutting member 1392 and cutting edge 1396 within the staple cartridge1380.

As described above, referring again to FIGS. 131, 133, and 134, theguide member 1370 can move relative to lock portion 1305′ and shaft1304, although, in various circumstances, the distal end of guide member1370 can be captured by and/or positioned against the lock portion1305′. Referring now to FIG. 140, a drive bar, such as drive bar 1390′,for example, can comprise a stop, such as stop 1395′, for example, whichcan be configured to contact guide member 1370 such that the distaladvancement of drive bar 1390′ and cutting member 1392 can be limited byguide member 1370. More particularly, in various embodiments, the stop1395′ can be configured to contact a stop datum, such as stop datum1399, for example, on the proximal end of guide member 1370 such that,when stop 1395′ contacts stop datum 1399, the drive bar 1390′ can nolonger be advanced, or at least significantly advanced, in the distaldirection into the staple cartridge 1380. When stop 1395′ contacts datum1399, and guide member 1370 is in contact with the lock portion 1305′,the final distal-most position of cutting edge 1396 can be largelydetermined by the predetermined, or set, distance 1397′ between the stopsurface 1395′ and cutting edge 1396, as described in greater detailfurther below. In various embodiments, the stop 1395′ can comprise adownwardly depending tab or projection which can include a perpendicularshoulder, for example, configured to engage a correspondingperpendicular shoulder of stop datum 1399, for example.

Further to the above, in at least one embodiment, with the stop surface1395′ of drive bar 1390′ in contact with the guide member 1370 and theguide member 1370 in contact with stop portion 1305′ of end effector1306, the final, distal-most position of the cutting edge 1396 relativeto the end 1384 of knife slot 1383 can be dictated by the predetermineddistance 1397′, the length of the guide slot in guide member 1370, andthe distance between datum 1331 and the distal end 1384 of knife slot1383. In various embodiments, the guide member 1370 can be comprised ofa sufficiently rigid material and geometry such that very little, ifany, deflection or deformation occurs within the guide slot in guidemember 1370 during use. Similarly, the end effector 1306 can becomprised of a sufficiently rigid material and geometry such that verylittle, if any, deflection or deformation occurs within the knife slot1383 during use. In certain embodiments, as a result, the guide slotwithin guide member 1370 and the knife slot 1383 can define a guide pathwhich has little variation in the length thereof regardless of theorientation of the end effector 1306. In at least some embodiments,however, there may be some variation in the length of the guide path.More particularly, although the guide member 1370 can be positionedagainst the stop portion 1305′, the relative alignment between the guideslot in guide member 1370 and the guide slot 1321 in lock portion 1305′may be different in the different orientations of end effector 1306resulting in different, or at least slightly different, guide pathlengths as discussed in greater detail below.

As discussed above, the orientation of end effector 1306 can affect therelative alignment between guide member 1370 and end effector 1306.Referring to FIG. 134 which illustrates the end effector 1306 in anapproximately 45 degree orientation, for example, and eventhough theguide member 1370 is in contact with the lock portion 1305′, a small gap1389 can exist between the distal end of guide member 1370 and the lockportion 1305′. When the end effector 1306 is articulated even further,as illustrated in FIG. 131 which illustrates the end effector 1306 in anapproximately 75 degree orientation, the gap 1389 between the guidemember 1370 and the lock portion 1305′ can become larger, albeitslightly, eventhough the guide member 1370 is still in contact with thelock portion 1305′. Such a change in the size of gap 1389 can result ina change in the length of the guide path comprising the guide slot inguide member 1370 and the knife slot 1383. Such changes in the guidepath length notwithstanding, the stop datum 1399 may provide a reliabledatum against which the distal advancement of drive bar 1390′ can bestopped and a reliable means for stopping the cutting edge 1396 at aconsistent position, and/or within a narrower range of positions, withinthe staple cartridge 1380 regardless of the orientation of the endeffector 1306. In certain circumstances, the stop 1395′ of drive bar1391 can contact the guide member 1370 and position the guide member1370 against the lock portion 1305′. Such circumstances can occur,referring to FIG. 133, when the end effector 1306 is in a straight, orat least substantially straight, orientation, for example.

Further to the above, referring now to FIGS. 140 and 141, the stop 1395′of drive bar 1391 can abut the datum surface 1399 of guide member 1370in order to stop the distal advancement of drive bar 1391 regardless ofthe orientation of end effector 1306. More particularly, referring toFIG. 140, the stop surface 1395′ can abut the datum surface 1399 whenthe end effector 1306 is in a straight orientation and, similarly,referring now to FIG. 141, the stop surface 1395′ of drive bar 1391 canalso abut the datum surface 1399 when the end effector 1306 is in anapproximately 66 degree orientation, for example. As the reader willnote when comparing FIGS. 140 and 141, further to the above, the guidemember 1370 has been pushed proximally by the articulation of endeffector 1306. When the guide member 1370 has been pushed proximally,the datum surface 1399 may also be pushed proximally which can shortenthe distance in which drive bar 1391 can travel distally.Correspondingly, when end effector 1306 is in a straight orientation,the distance in which drive bar 1391 can travel distally can be longer.In various embodiments, as a result of the above, the distance in whichthe drive bar 1391 can be displaced distally may decrease as thearticulation angle of end effector 1306 is increased. In summary, whenthe end effector 1306 is in an articulated position, the cutting member1392 may have a more distal starting position; however, such a moredistal starting position may be compensated for by the proximally-moveddatum surface 1399 which can limit the distal displacement of thecutting member 1392 such that the final distal-most position of cuttingmember 1392 is the same as, or within a very close range with respectto, the final distal-most position of cutting member 1392 when endeffector 1306 is in a straight orientation. Likewise, when end effector1306 is in a straight orientation, the cutting member 1392 may have amore proximal starting position; however, such a more proximal startingposition may be compensated for by the more distal datum surface 1399which can provide for a longer distal displacement of the cutting member1392 such that the final distal-most position of cutting member 1392 isthe same as, or within a very close range with respect to, the finaldistal-most position of cutting member 1392 when end effector 1306 is inan articulated orientation.

As discussed above, referring again to FIG. 138, it may be desirable tostop the knife edge 1396 of cutting member 1392 short of end datum 1386.In various embodiments, referring now to FIG. 142, a surgical staplinginstrument, such as surgical instrument 1400, for example, can comprisea firing system driven by a motor, such as motor 1410, for example. Inuse, the motor 1410 can be operated so as to advance a cutting member,such as cutting member 1392, for example, through an end effector, suchas end effector 1306, for example, to the same, or at leastsubstantially the same, final distal position within end effector 1306such that knife edge 1396 is stopped short of end datum 1398 regardlessof the angle in which the end effector 1306 has been articulated. Incertain embodiments, further to the above, the motor 1410 can bepositioned within a handle of the surgical instrument 1400, for example.The surgical instrument 1400 can further comprise a firing switch, ortrigger, positioned on and/or operably coupled with the surgicalinstrument handle, for example, wherein the switch, or trigger, can beoperated in order to operably couple motor 1410 with a power source,such as a battery, for example, which can also be positioned within thehandle. In use, as described in greater detail below, the firing switch,or trigger, can be operated to supply power from the power source to themotor 1410 in order to advance and/or retract a firing rod 1466, thedrive bar 1390, and the cutting member 1392.

In various embodiments, further to the above, the motor 1410 cancomprise a drive shaft 1411 operably coupled with a pinion gear 1412,wherein the motor 1410 can be configured to rotate drive shaft 1411 andpinion gear 1412 in a first, or clockwise, direction and/or in a second,counter-clockwise, direction. Referring again to FIG. 142, pinion gear1412 can be operably coupled with a rack 1413, wherein the rotation ofpinion gear 1412 can drive rack 1413 in a distal direction D and/or aproximal direction P depending on the direction in which pinion gear1412 is rotated. In various embodiments, the pinion gear 1412 and therack 1413 can each comprise teeth which can co-operate with one anotherto transmit the rotational motion of gear 1412 to linear, or at leastsubstantially linear, motion of rack 1413. As also illustrated in FIG.142, the firing drive can further comprise a firing rod 1466 operablycoupled with the rack 1413 and, as described in greater detail furtherbelow, the drive bar 1390 can be operably coupled with the firing rod1466 such that the movement of rack 1413 can be transmitted to firingrod 1466 and drive bar 1390. Similar to the above, referring now to FIG.143, the drive bar 1390 can be operably coupled with cutting member 1392such that distal movement of rack 1413 can move cutting member 1392distally and, correspondingly, proximal movement of rack 1413 can movecutting member 1392 proximally.

In use, further to the above, a surgeon can operate the surgicalinstrument 1400 by manipulating a firing switch, or trigger, on thesurgical instrument handle, for example, in order to advance the cuttingmember 1392 and, ultimately, staple and/or incise tissue positionedwithin the end effector of the surgical instrument. In variousembodiments, the surgical instrument 1400 can further comprise acomputer which can comprise one or more inputs, wherein at least one ofsuch inputs can be operably coupled with the firing switch such that thecomputer can detect the operation of the firing switch. In certainembodiments, the computer can be positioned within the surgicalinstrument handle, for example. In at least one embodiment, theoperation of the switch can close a circuit which, in response thereto,the computer can command the motor 1410 to rotate in a direction whichmoves the rack 1413 in a proximal direction, i.e., direction P. Moreparticularly, the computer can, in response to the switch input,complete a circuit allowing a voltage potential to be applied to themotor 1410 by the battery which, as a result, can allow the motor 1410to rotate shaft 1411 and pinion gear 1412. In any event, when cuttingmember 1392 is pulled proximally by rack 1413, the cutting member 1392can be brought into contact with a datum, such as datum stop or surface1398, for example, in the end effector 1306. Once cutting member 1392 isin contact with datum stop 1398, and/or once the computer of thesurgical instrument 1400 has detected that cutting member 1392 is incontact with the datum surface 1398, the computer can, in at least oneembodiment, open the circuit between the power source and the motor 1410such that the motor 1410 no longer rotates pinion gear 1412 and suchthat pinion gear 1412 no longer drives rack 1413 proximally.

In various embodiments, further to the above, the surgical instrument1400 can further comprise an encoder system which can detect when thecutting member 1392 has contacted the datum surface 1398. In at leastone embodiment, the rack 1413 can comprise a plurality of detectableelements 1414 arranged in a linear array positioned thereon and/ortherein, wherein the encoder system can further comprise an encodersensor 1415 configured to detect the detectable elements 1414 as theypass by the encoder sensor 1415. In some embodiments, the detectableelements 1414 can comprise iron which, when the elements 1414 pass infront of sensor 1415, can create disruptions in a magnetic field whichare detected by the encoder sensor 1415. In certain embodiments, thedetectable elements 1414 can comprise visible demarcations, such asprojections, recesses, and/or colored lines, for example, which can bedetected by the encoder sensor 1415. In any event, the encoder sensor1415 can be operably coupled with the computer such that the computercan count the detectable elements 1414 detected by sensor 1415 as rack1413 is retracted, or moved in a proximal direction P. Moreparticularly, in at least one embodiment, the encoder sensor 1415 can beoperably coupled with at least one of the computer inputs such that thecomputer can receive one or more signals from the encoder sensor 1415.In any event, in various embodiments, the detectable elements 1414 canbe positioned at predetermined, or set, distances apart from one anothersuch that the detection of sequential detectable elements 1414 canindicate to the computer that the rack 1413 has been moved a set, orunit, distance. In at least one embodiment, such a set, or unit,distance can comprise 1 mm, for example. In certain embodiments, themotor can comprise an encoder motor including an encoder systemintegrally incorporated therein wherein the encoder can measure torotation of motor shaft 1411, for example, and, based on the size andconfiguration of pinion gear 1412, estimate the proximal and/or distalmovement of rack 1413.

In any event, the computer of the surgical instrument 1400 can beconfigured to compare the output commands sent to the motor 1410 to theinput signals received from the encoder sensor 1415 in order todetermine whether there is a difference between the expected positionand the actual position of the rack 1413 and, correspondingly, theexpected and actual positions of cutting member 1392. By way of example,FIG. 145 provides a graphical representation of what the computer maydetect, i.e., a first range 1416 a which indicates that rack 1413 isbeing retracted toward datum stop 1398 and a second range 1416 b whichindicates that cutting member 1392 is in contact with datum stop 1398and/or is only moving slightly due to the deformation of datum stop 1398and/or cutting member 1392, for example. Referring again to FIG. 145,the computer of surgical instrument 1400 can compare the expectedmovement of rack 1413 based on the commands, or output, being given tomotor 1410, as depicted by line 1417, to the detected movement of rack1413 based on the input of the encoder sensor 1415, as depicted by line1418, and, when a sufficient difference exists between the expectedmovement and the actual movement of rack 1413, the computer can operablydecouple the power source from the motor 1410 and/or otherwise commandthe motor 1410 to stop rotating pinion 1412. At such point, the computerof surgical instrument 1400 can record the position of the rack 1413,and cutting member 1392, as being in a ‘datum position’. In variousembodiments, the computer can comprise memory storage, such as anon-volatile random access memory (NVRAM) chip, for example, which canbe configured to store such information, and/or any other informationregarding the position of the rack 1413 and cutting member 1392 at anyother point during the operation of the surgical instrument.

Once cutting member 1392 is in contact with datum stop 1398, thecomputer can instruct the motor 1410 to rotate pinion gear 1412 in theopposite direction in order to advance rack 1413 distally, i.e., indirection D. In at least one embodiment, the computer can reverse thepolarity of the voltage applied to motor 1410 in order to rotate piniongear 1412 in the opposite direction. In any event, the computer caninstruct motor 1410 to advance cutting member 1392 a predetermined, orset, distance relative to datum stop 1398. In at least one suchembodiment, the computer can allow a predetermined, or set, voltageand/or current to be supplied to the motor 1410 from the power sourcefor a predetermined, or set, duration which can, in variouscircumstances, advance the cutting member 1392 the predetermineddistance. In certain embodiments, the magnitude and/or duration, forexample, of the voltage and/or current supplied to the motor 1410 can beadjusted based on feedback supplied to the computer. In at least oneembodiment, further to the above, the encoder sensor 1415 can beconfigured to relay the actual, or at least perceived, displacement andposition of the rack 1413 to the computer such that the computer cancompare the actual position of the rack 1413 to its expected positionand, correspondingly, compare the actual and expected positions of theknife edge 1396. In the event that the computer determines that theposition of the knife edge 1396, for example, lags its expectedposition, the computer can increase the duration and/or magnitude ofpower supplied to the motor 1410 such that the knife edge 1396 arrivesat its expected position, or at least substantially close thereto.Alternatively, in the event that the computer determines that theposition of the knife edge 1396 leads its expected position, thecomputer can shorten the duration and/or decrease the magnitude of powerbeing supplied to the motor 1410 such that the knife edge 1396 does notsurpass, or at least substantially surpass, its expected position.

In various embodiments, further to the above, the predetermined, or set,distance in which the cutting member 1392 is advanced relative to thedatum stop 1398 can be the same, or at least substantially the same,distance regardless of the articulation angle, if any, of end effector1306. In various circumstances, as a result, the knife edge 1396 can bestopped at the same, or at least substantially the same, position shortof end datum 1386. As the reader will note, referring to FIGS. 138 and143, the datum stop 1398 and end datum 1386 are both positioned distallywith respect to the articulation joint of the surgical instrument and,as a result, the potential shifting of the articulation jointcomponents, such as guide member 1370, for example, as discussed above,may not impact the relative arrangement of the datums 1386 and 1398. Inat least one exemplary embodiment, the datum stop 1398 can be positionedwithin the staple cartridge channel of the end effector 1306 and the enddatum 1398 can be determined by certain features of the staple cartridge1380 positioned within the staple cartridge channel, as discussed above.In certain other embodiments, the datum stop 1398 and the end datum 1386can both be defined by features of a staple cartridge while, in someembodiments, the datums 1398 and 1386 can be defined by features of thestaple cartridge channel, for example. In any event, when the cuttingmember 1392 is positioned against the datum stop 1398 and then advanceddistally the predetermined distance, the cutting member 1392, and knifeedge 1396, can be positioned reliably, or at least substantiallyreliably, relative to the end datum 1386.

In various embodiments, referring now to FIG. 144, the interconnectionbetween the distal end of firing rod 1466 and the proximal end of drivebar 1390 can permit relative movement therebetween. In at least oneembodiment, the drive bar portion 1391 of drive bar 1390 can comprise aflange, or tab, 1369 depending therefrom which can be positioned withina slot, or groove, 1467 in the firing rod 1466, for example. Asillustrated in FIG. 144, the width W2 of the slot 1467 is wider than thewidth W1 of the tab 1369 such that the tab 1369 can slide proximallyand/or distally, for example, within the slot 1467. In certainembodiments, as a result, one or more gaps can be present between thesides 1369p and 1369d of tab 1369 and the sides 1467p and 1467d of slot1467. Such gaps, in various circumstances, may facilitate thearticulation of the end effector 1306, for example, by allowing at leastsome relative movement between the firing rod 1466 and the drive bar1390 so as to prevent, or at least reduce the possibility of the drivebar 1390 buckling undesirably and/or the possibility of drive bar 1390undesirably resisting the articulation of end effector 1306. Moreparticularly, in at least some circumstances, the drive bar 1390 may bemoved proximally during the articulation of end effector 1306 and, in atleast one embodiment, the slot 1467 can be sized and configured toaccommodate such proximal movement of drive bar 1390. As discussedfurther above, the distance in which the drive bar 1390 moves proximallymay be directly proportional to the degree of articulation of endeffector 1306, i.e., larger articulations of end effector 1306 mayresult in more proximal movement (FIG. 146 b) of drive bar 1390 and,correspondingly, smaller articulations of end effector 1306 may resultin less proximal movement (FIG. 146 a). In at least one embodiment, thewidth W2 of slot 1467 may be such that the proximal side 1369 p of tab1369 does not come into contact with the proximal wall 1467 p of slot1467. In any event, in various embodiments, the firing drive of thesurgical instrument 1400 discussed above may compensate or account forany gaps between the tab 1369 and the slot 1467, for example, in orderto position the cutting member 1392 in a desired position relative toend datum 1386.

An exemplary sequence of operating a surgical instrument in accordancewith some of the embodiments described above is now provided. In use, asurgeon can unlock the end effector 1306 and articulate the end effector1306 by positioning it against tissue within the surgical site andapplying a force in distal direction along the axis of shaft 1304 suchthat the end effector 1306 pivots relative to shaft 1304. Once endeffector 1306 has been suitably articulated, the end effector 1306 canbe locked into position, the end effector 1306 can be positioned suchthat tissue is positioned intermediate the staple cartridge 1380 and theanvil 1312, and the anvil 1312 can be closed in order to clamp thetissue. As a result of the articulation of end effector 1306, as will bediscussed in greater detail below, the drive bar 1390 may moveproximally and, as a result, a gap may be created between side 1368 d oftab 1369 and side 1467 d of slot 1467. Once the surgeon is satisfiedwith the positioning of the tissue within the closed end effector 1306,the surgeon can activate a firing switch, or trigger, which can bedetected by the computer of the surgical instrument. As described above,the computer can instruct the motor 1410 to retract rack 1413proximally. In various circumstances, the computer can utilize pulsewidth modulation in order to limit the power supplied to motor 1410 andpull the rack 1413 slowly. When the rack 1413 is moved proximally, therack 1413 can pull firing rod 1466 proximally such that side 1467 d ofslot 1467 comes into contact with the side 1368 d of tab 1369 and, as aresult, the gap between side 1467 d and side 1368 d can be eliminated.Once side 1467 d is in contact with side 1368 d, the rack 1413 andfiring rod 1466 can pull cutting member 1392 proximally until cuttingmember 1392 is in contact with datum stop 1398. In various embodiments,the pulse width modulation applied to motor 1410 can be calibrated suchthat the force applied to rack 1413 by motor 1410 does not exceed acertain maximum or peak force, such as approximately 30 lbf and/or 40lbf, for example. By setting such a maximum force, in at least oneembodiment, damage to rack 1413, firing rod 1466, driver bar 1390, andcutting member 1392, for example, may be avoided. In any event, theencoder system and the computer of the surgical instrument, describedabove, can detect when the cutting member 1392 has come into contactwith the datum stop 1398 and the power being supplied to the motor 1410can be disconnected. In certain embodiments, further to the above, theencoder system and the computer can determine whether the cutting member1392 is moving freely toward the datum stop 1398 or whether the cuttingmember 1392 has come into contact with the stop datum 1398 and thatcertain components, such as stop datum 1398 and cutting member 1392,have begun to at least one of elastically or plastically deform. In thisreference position, the cutting member 1392 is in contact with the datumstop 1398 (FIG. 143) and there exists a gap 1469 between the side 1467 pof slot 1467 and the side 1369 p of the tab 1369. In variousembodiments, the computer can instruct the motor 1410 to advance therack 1413 in the distal direction D such that side 1467 p of slot 1467comes into contact with the side 1369 p of the tab 1369. In at least onesuch embodiment, the rack 1413 can be advanced distally a predetermined,or set, distance, such as approximately 0.15″, for example, in order toeliminate gap 1469 and, possibly, an additional distance, such asapproximately 0.025″, for example, in order to assure that the gap 1469has been eliminated and, in at least one embodiment, assure that cuttingmember 1392 has at least slightly broken contact with the datum stop1398, for example. This new position can be recorded by the computer asyet another reference position and can be referred to as the “home”position. In various embodiments, the motor 1410 can pause the movementof the cutting member 1392 at the home position and/or continue movingcutting member 1392 distally through its predetermined distance in acontinuous manner. As discussed above, the rack 1413, and cutting member1392, can be moved distally the same distance with respect to the datumstop 1398 and/or home position of the cutting member 1392 regardless ofthe articulation angle, if any, of the end effector 1306. Accordingly,the cutting member 1392, and knife edge 1396 thereof, may moved into thesame final distal position relative to the end datum 1398 and/or distalend 1384 of knife slot 1383, for example. In any event, after thecutting member 1392 has been advanced to its distal-most position, thecomputer can instruct the motor 1410 to retract the rack 1413 andcutting member 1392 proximally such that the anvil 1312 can bere-opened. In certain embodiments, the firing switch, or trigger, of thesurgical instrument, for example, can be manipulated such that thecomputer instructs the motor 1410 to stop the cutting member 1392 shortof its final distal position

In various embodiments, as described above, the position of the cuttingmember 1392 relative to datum stop 1398 in the proximal end of thestaple cartridge channel, or staple cartridge 1380, can be determined,or tested, by the methods described above. In certain embodiments, theposition of the cutting member 1392 relative to another datum, such as adatum in the distal end of the staple cartridge channel and/or staplecartridge 1380, for example, can be determined, or tested. In at leastone such embodiment, the distance between the datum stop 1398 and thedistal end of the staple cartridge channel can be determined byadvancing the cutting member 1392 distally from the datum stop 1398and/or home position, for example, until the cutting member 1392contacts the distal end of the staple cartridge channel. Once in thisreference position, the computer can store this position in its memoryand, based on such information, calculate the maximum cut length of thecutting member 1392 that is possible and adjust the predetermined, orset, distance that is desired for the cutting member 1392 to travelduring use. Such a test can be performed before a staple cartridge ispositioned within the staple cartridge channel and before the endeffector is positioned within a patient, for example.

As described above, a surgical instrument can comprise an end effectorwhich is articulatable relative to a shaft of the surgical instrument.As also described above, the end effector can be selectively locked intoposition relative to the shaft. Referring now to FIGS. 147 and 148, asurgical instrument can comprise an end effector including end effectorlock member 1500 which can be articulated about pivot 1502. Similar toend effector lock member 300, end effector lock member 1500 can comprisea plurality of teeth 1512 and a plurality of recesses 1514 positionedaround a perimeter of lock member 1500 which can be rotated about pivot1502 when the end effector is articulated. In at least one suchembodiment, each recess 1514 can be positioned intermediate two teeth1512. In various embodiments, the surgical instrument can furthercomprise a lock member 1538 which can comprise a tooth 1536 configuredto be inserted into one of the recesses 1514 in end effector lock member1500. In use, the tooth 1536 can be disengaged from the recesses 1514 inorder to permit the end effector, including lock member 1500, to berotated into a desired position wherein the lock 1538 can then beadvanced distally such that the tooth 1536 is inserted into and engagedwith a recess 1514. In certain circumstances, the lock tooth 1536 maynot be aligned with a recess 1514 when the lock 1538 is advanceddistally. In certain embodiments, the lock tooth 1536 and/or the endeffector lock teeth 1512 can comprise one or more beveled or angledsurfaces which can be configured to cause the end effector lock member1500 to rotate slightly, or index, into a position in which a recess1514 is aligned with the lock tooth 1536.

The devices disclosed herein can be designed to be disposed of after asingle use, or they can be designed to be used multiple times. In eithercase, however, the device can be reconditioned for reuse after at leastone use. Reconditioning can include any combination of the steps ofdisassembly of the device, followed by cleaning or replacement ofparticular pieces, and subsequent reassembly. In particular, the devicecan be disassembled, and any number of the particular pieces or parts ofthe device can be selectively replaced or removed in any combination.Upon cleaning and/or replacement of particular parts, the device can bereassembled for subsequent use either at a reconditioning facility, orby a surgical team immediately prior to a surgical procedure. Thoseskilled in the art will appreciate that reconditioning of a device canutilize a variety of techniques for disassembly, cleaning/replacement,and reassembly. Use of such techniques, and the resulting reconditioneddevice, are all within the scope of the present application.

Preferably, the invention described herein will be processed beforesurgery. First, a new or used instrument is obtained and if necessarycleaned. The instrument can then be sterilized. In one sterilizationtechnique, the instrument is placed in a closed and sealed container,such as a plastic or TYVEK bag. The container and instrument are thenplaced in a field of radiation that can penetrate the container, such asgamma radiation, x-rays, or high-energy electrons. The radiation killsbacteria on the instrument and in the container. The sterilizedinstrument can then be stored in the sterile container. The sealedcontainer keeps the instrument sterile until it is opened in the medicalfacility.

While this invention has been described as having exemplary designs, thepresent invention may be further modified within the spirit and scope ofthe disclosure. This application is therefore intended to cover anyvariations, uses, or adaptations of the invention using its generalprinciples. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this invention pertains.

1. A surgical stapler, comprising: a channel configured to receive astaple cartridge comprising staples removably stored therein, whereinsaid channel comprises: a distal end; a proximal portion; and a stop; ananvil configured to deform staples ejected from the staple cartridge,wherein said anvil comprises a distal end and a proximal portion,wherein said proximal portion of said anvil is pivotably coupled to saidproximal portion of said channel, and wherein said anvil is rotatablebetween an open position and a closed position; a closure member movablebetween a first position and a second position, wherein said closuremember is configured to move said anvil between said open position andsaid closed position when said closure member is moved between saidfirst position and said second position, and wherein said closure membercomprises: a body; a first camming portion extending from said body afirst distance toward said distal end of said channel, wherein saidfirst camming portion is configured to be at least partially positionedaround said anvil when said closure member is in said second position;and a second camming portion extending from said body a second distancetoward said distal end of said channel, wherein said first distance islarger than said second distance, wherein said second camming portion isconfigured to be at least partially positioned around said channel andadjacent to said stop when said closure member is in said secondposition.
 2. The surgical stapler of claim 1, further comprising ahandle, a trigger, and a drive member operably coupled with said triggerand said closure member, wherein an actuation of said trigger isconfigured to move said closure member between said first position andsaid second position.
 3. The surgical stapler of claim 1, furthercomprising said staple cartridge.
 4. The surgical stapler of claim 1,wherein said anvil comprises an arcuate outer surface, and wherein saidfirst camming portion comprises an arcuate inner portion configured toslide over said arcuate outer surface.
 5. The surgical stapler of claim4, wherein said channel comprises an arcuate outer surface, and whereinsaid second camming portion comprises an arcuate inner portionconfigured to slide over said arcuate outer surface of said channel. 6.A surgical instrument, comprising: a shaft comprising a drive bar and afirst guide slot, wherein said first guide slot is configured to receiveat least a portion of said drive bar; an end effector pivotably coupledto said shaft about a pivot joint, said end effector rotatable aboutsaid pivot joint in a first direction and a second direction, said endeffector comprising: a staple cartridge attachment portion configured toreceive a staple cartridge; a second guide slot configured to receive atleast a portion of said drive bar; a first recess positioned on a firstside of said second guide slot; and a second recess positioned on asecond side of said second guide slot; and a guide member configured tomove independently of said shaft and said end effector, said guidemember, comprising: a third guide slot configured to receive at least aportion of said drive bar; a first catch positioned on a first side ofsaid third guide slot, wherein said first catch is configured to bereceived in said first recess of said end effector when said endeffector is rotated in said first direction; and a second catchpositioned on a second side of said third guide slot, wherein saidsecond catch is configured to be received in said second recess of saidend effector when said end effector is rotated in said second direction.7. The surgical instrument of claim 6, wherein said guide member furthercomprises a boss extending therefrom, wherein said end effector furthercomprises a boss slot configured to receive said boss, and wherein saidboss slot comprises a sidewall configured to limit the movement of saidboss and said guide member relative to said end effector.
 8. Thesurgical instrument of claim 7, wherein said boss is configured to beengaged with said sidewall when said first catch is positioned in saidfirst recess or said second catch is positioned in said second recess.9. The surgical instrument of claim 7, wherein said guide member furthercomprises a second boss extending therefrom, wherein said shaft furthercomprises a second boss slot configured to receive said second boss, andwherein said second boss slot comprises a second sidewall configured tolimit the movement of said second boss and said guide member relative tosaid shaft.
 10. The surgical instrument of claim 6, wherein said firstrecess comprises a first sidewall configured to engage said first catchand rotate said guide member in said first direction when said endeffector is rotated in said first direction, and wherein said secondrecess comprises a second sidewall configured to engage said secondcatch and rotate said guide member in said second direction when saidend effector is rotated in said second direction.
 11. A surgicalinstrument, comprising: a shaft comprising a drive bar and a first guideslot, wherein said first guide slot is configured to receive at least aportion of said drive bar; an end effector pivotably coupled to saidshaft about a pivot joint, said end effector rotatable about said pivotjoint in a first direction and a second direction, said end effectorcomprising a staple cartridge attachment portion configured to receive astaple cartridge; and a guide member configured to move independently ofsaid shaft and said end effector, said guide member, comprising: asecond guide slot configured to receive at least a portion of said drivebar; and a projection, wherein said shaft comprises a recess configuredto receive said projection, wherein said end effector is configured topush said guide member toward said shaft and position said projection insaid recess when said end effector is moved in said first direction orsaid second direction, and wherein said recess comprises a sidewallconfigured to limit the movement of said projection relative to saidrecess and said shaft.
 12. The surgical instrument of claim 11, whereinsaid guide member further comprises a boss extending therefrom, whereinsaid shaft further comprises a boss slot configured to receive saidboss, and wherein said boss slot comprises a sidewall configured tolimit the movement of said boss and said guide member relative to saidshaft.
 13. The surgical instrument of claim 11, wherein said endeffector further comprises: a third guide slot configured to receive atleast a portion of said drive bar; a first recess positioned on a firstside of said second guide slot; and a second recess positioned on asecond side of said second guide slot; and wherein said guide memberfurther comprises: a first catch positioned on a first side of saidthird guide slot, wherein said first catch is configured to be receivedin said first recess of said end effector when said end effector isrotated in said first direction; and a second catch positioned on asecond side of said third guide slot, wherein said second catch isconfigured to be received in said second recess of said end effectorwhen said end effector is rotated in said second direction.
 14. Thesurgical instrument of claim 13, wherein said guide member furthercomprises a second boss extending therefrom, wherein said end effectorfurther comprises a second boss slot configured to receive said secondboss, and wherein said second boss slot comprises a second sidewallconfigured to limit the movement of said second boss and said guidemember relative to said end effector.
 15. The surgical instrument ofclaim 14, wherein said second boss is configured to be engaged with saidsecond sidewall when said first catch is positioned in said first recessor said second catch is positioned in said second recess.